Buffer Overflow
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
How It Works
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions. This overwrites whatever data or code exists there, corrupting program state and potentially giving attackers control over execution flow.
Stack-based overflows are the most common variant. When a function allocates a fixed-size buffer on the stack and then copies user-controlled input without proper bounds checking, attackers can overflow past the buffer to overwrite the function's return address. When the function completes, instead of returning to legitimate code, execution jumps to attacker-specified memory containing malicious shellcode. Heap-based overflows work differently—they corrupt heap metadata like chunk size fields or free list pointers, leading to arbitrary memory writes when the allocator processes the corrupted structures.
Modern exploitation bypasses defensive mechanisms through techniques like Return-Oriented Programming (ROP), which chains together existing code snippets to avoid non-executable memory protections. Attackers may also use heap spraying to reliably position shellcode at predictable addresses, defeating address randomization.
Impact
- Remote code execution — attacker gains ability to run arbitrary commands with the privileges of the vulnerable process
- Privilege escalation — exploiting kernel or setuid program overflows to gain root/SYSTEM access
- Denial of service — crashes and memory corruption that render systems unusable
- Information disclosure — reading sensitive data from adjacent memory regions that should be inaccessible
- Authentication bypass — overwriting security-critical variables like permission flags or user IDs
Real-World Examples
Fortinet FortiOS suffered a critical buffer overflow (CVE-2025-32756) that allowed unauthenticated remote attackers to execute code as root on firewalls and VPN gateways. Attackers actively exploited this to compromise enterprise network perimeters before patches were available.
The Slammer worm from 2003 exploited a stack overflow in Microsoft SQL Server, spreading to 75,000 hosts in ten minutes by sending a single malformed UDP packet that overwrote the return address with shellcode. No authentication was required.
OpenSSH historically contained a heap overflow in challenge-response authentication that allowed pre-authentication remote root compromise on Unix systems, demonstrating how memory corruption in privileged network services creates maximum impact scenarios.
Mitigation
- Memory-safe languages — Rust, Go, and modern managed languages prevent buffer overflows by design through automatic bounds checking
- Stack canaries — random values placed before return addresses that detect corruption before control transfer
- Address Space Layout Randomization (ASLR) — randomizes memory locations making exploitation less reliable
- Data Execution Prevention (DEP/NX) — marks memory regions as non-executable, preventing direct shellcode execution
- Bounds checking — validate input sizes before copying, use safe functions like
strncpyinstead ofstrcpy - Fuzzing and static analysis — automated testing to discover overflows before deployment
Recent CVEs (36583)
xrdp is an open source remote desktop protocol server. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative. Rated medium severity (CVSS 6.6), this vulnerability is remotely exploitable. No vendor patch available.
Memory safety bugs present in Firefox 117, Firefox ESR 115.2, and Thunderbird 115.2. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In a non-standard configuration of Firefox, an integer overflow could have occurred based on network traffic (possibly under influence of a local unprivileged webpage), leading to an out-of-bounds. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A compromised content process could have provided malicious data in a `PathRecording` resulting in an out-of-bounds write, leading to a potentially exploitable crash in a privileged process. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
A compromised content process could have provided malicious data to `FilterNodeD2D1` resulting in an out-of-bounds write, leading to a potentially exploitable crash in a privileged process. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Potential buffer overflow vulnerabilities n the Zephyr Bluetooth subsystem. Rated critical severity (CVSS 9.6), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Potential off-by-one buffer overflow vulnerability in the Zephyr fuse file system. Rated critical severity (CVSS 10.0), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the ssid parameter in the form_fast_setting_wifi_set function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the speed_dir parameter in the formSetSpeedWan function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the formSetClientState function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the security parameter in the formWifiBasicSet function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the mac parameter in the GetParentControlInfo function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the domain parameter in the add_white_node function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the timeZone parameter in the fromSetSysTime function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the deviceId parameter in the addWifiMacFilter function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the schedEndTime parameter in the setSchedWifi function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain multiple stack overflows in the formSetMacFilterCfg function via the macFilterType and deviceList parameters. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC10U v1.0 US_AC10UV1.0RTL_V15.03.06.49_multi_TDE01 was discovered to contain a stack overflow via the list parameter in the fromSetIpMacBind function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Memory overwriting vulnerability in the security module. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An out-of-bounds read was addressed with improved bounds checking. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
The issue was addressed with improved bounds checks. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An out-of-bounds read was addressed with improved input validation. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
The issue was addressed with improved checks. Rated medium severity (CVSS 4.3), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A buffer overflow issue was addressed with improved memory handling. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Two potential buffer overflow vulnerabilities at the following locations in the Zephyr eS-WiFi driver source code. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An array indexing vulnerability was found in the netfilter subsystem of the Linux kernel. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
A heap out-of-bounds read flaw was found in builtin.c in the gawk package. Rated high severity (CVSS 7.1), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An out-of-bounds write vulnerability exists in the allocate_buffer_for_jpeg_decoding functionality of Accusoft ImageGear 20.1. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A heap-based buffer overflow vulnerability exists in the pictwread functionality of Accusoft ImageGear 20.1. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An out-of-bounds write vulnerability exists in the dcm_pixel_data_decode functionality of Accusoft ImageGear 20.1. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A heap-based buffer overflow vulnerability exists in the create_png_object functionality of Accusoft ImageGear 20.1. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An out-of-bounds write vulnerability exists in the tiff_planar_adobe functionality of Accusoft ImageGear 20.1. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A stack-based buffer overflow vulnerability exists in the tif_processing_dng_channel_count functionality of Accusoft ImageGear 20.1. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A heap-based buffer overflow vulnerability exists in the CreateDIBfromPict functionality of Accusoft ImageGear 20.1. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
General Device Manager 2.5.2.2 is vulnerable to Buffer Overflow. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
DoS vulnerability in the PMS module. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
DoS vulnerability in the PMS module. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
DoS vulnerability in the PMS module. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cesanta mjs v2.20.0 was discovered to contain a function pointer hijacking vulnerability via the function mjs_get_ptr(). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The package `github.com/gomarkdown/markdown` is a Go library for parsing Markdown text and rendering as HTML. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
The fix for XSA-423 added logic to Linux'es netback driver to deal with a frontend splitting a packet in a way such that not all of the headers would come in one piece. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Out-of-bounds Write vulnerability could allow attackers to write data beyond allocated buffer boundaries leading to code execution or crashes.
A buffer copy without checking size of input vulnerability has been reported to affect QNAP operating systems. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A buffer copy without checking size of input vulnerability has been reported to affect QNAP operating system. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Delta Electronics DIAScreen may write past the end of an allocated buffer while parsing a specially crafted input file. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Due to failure in validating the length provided by an attacker-crafted PPD PostScript document, CUPS and libppd are susceptible to a heap-based buffer overflow and possibly code execution. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter removeRuleList in form2IPQoSTcDel. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-823G v1.0.2B05 was discovered to contain a stack overflow via parameter TXPower and GuardInt in SetWLanRadioSecurity. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter sip_address in ipportFilter. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter flag_5G in showMACfilterMAC. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter nvmacaddr in form2Dhcpip.cgi. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter macCloneMac in setMAC. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-816 A2 v1.10CNB05 was discovered to contain a stack overflow via parameter statuscheckpppoeuser in dir_setWanWifi. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DIR-823G v1.0.2B05 was discovered to contain a stack overflow via parameter StartTime and EndTime in SetWifiDownSettings. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Buffer Overflow vulnerability in JerryScript version 3.0, allows remote attackers to execute arbitrary code via ecma_stringbuilder_append_raw component at /jerry-core/ecma/base/ecma-helpers-string.c. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A buffer overflow vulnerability exists in the Rockwell Automation select 1756-EN* communication devices. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
D-LINK DWL-6610 FW_v_4.3.0.8B003C was discovered to contain a stack overflow vulnerability in the function update_users. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link device DI-7200GV2.E1 v21.04.09E1 was discovered to contain a stack overflow via the hi_up parameter in the qos_ext.asp function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link device DI-7200GV2.E1 v21.04.09E1 was discovered to contain a stack overflow via the id parameter in the yyxz.data function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link device DI-7200GV2.E1 v21.04.09E1 was discovered to contain a stack overflow via the prev parameter in the H5/login.cgi function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link device DI-7200GV2.E1 v21.04.09E1 was discovered to contain a stack overflow via the popupId parameter in the H5/hi_block.asp function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link device DI-7200GV2.E1 v21.04.09E1 was discovered to contain a stack overflow via the fn parameter in the tgfile.asp function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
D-Link DI-7200GV2.E1 v21.04.09E1 was discovered to contain a stack overflow via the zn_jb parameter in the arp_sys.asp function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The code that processes control channel messages sent to `named` calls certain functions recursively during packet parsing. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Write vulnerability could allow attackers to write data beyond allocated buffer boundaries leading to code execution or crashes.
NVIDIA DGX H100 baseboard management controller (BMC) contains a vulnerability in a web server plugin, where an unauthenticated attacker may cause a stack overflow by sending a specially crafted. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
NVIDIA DGX H100 BMC contains a vulnerability in the host KVM daemon, where an authenticated local attacker may cause corruption of kernel memory. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
blurhash-rs is a pure Rust implementation of Blurhash, software for encoding images into ASCII strings that can be turned into a gradient of colors representing the original image. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
phonenumber is a library for parsing, formatting and validating international phone numbers. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. Public exploit code available and no vendor patch available.
A flaw was found in glibc. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required. Public exploit code available and no vendor patch available.
Buffer Overflow vulnerability in Tenda AC10V4 v.US_AC10V4.0si_V16.03.10.13_cn_TDC01 allows a remote attacker to cause a denial of service via the mac parameter in the GetParentControlInfo function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Contiki-NG is an operating system for internet-of-things devices. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Contiki-NG is an operating system for internet-of-things devices. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Dell PowerEdge BIOS and Dell Precision BIOS contain a buffer overflow vulnerability. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
An issue was discovered in OPSWAT MetaDefender KIOSK 4.6.1.9996. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An out-of-bounds read flaw was found in the parse_module function in bfd/vms-alpha.c in Binutils. Rated high severity (CVSS 7.1), this vulnerability is no authentication required, low attack complexity.
A flaw was found in GLib. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A heap buffer overflow vulnerability in Wibu CodeMeter Runtime network service up to version 7.60b allows an unauthenticated, remote attacker to achieve RCE and gain full access of the host system. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
**DISPUTED**A failure in the -fstack-protector feature in GCC-based toolchains that target AArch64 allows an attacker to exploit an existing buffer overflow in dynamically-sized local variables in. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, no authentication required. Public exploit code available and no vendor patch available.
Acrobat Reader versions 23.003.20284 (and earlier), 20.005.30516 (and earlier) and 20.005.30514 (and earlier) are affected by an out-of-bounds write vulnerability that could result in arbitrary code. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
DHCP Server Service Information Disclosure Vulnerability. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Internet Connection Sharing (ICS) Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity.
Windows Miracast Wireless Display Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity.
Windows Common Log File System Driver Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Common Log File System Driver Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Kernel Information Disclosure Vulnerability. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity.
DHCP Server Service Information Disclosure Vulnerability. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Visual Studio Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
3D Builder Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.