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 (36633)
Cscape Envision RV version 4.60 is vulnerable to an out-of-bounds read vulnerability when parsing project (i.e. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
All versions of the package node-bluetooth are vulnerable to Buffer Overflow via the findSerialPortChannel method due to improper user input length validation. 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.
All versions of the package node-bluetooth-serial-port are vulnerable to Buffer Overflow via the findSerialPortChannel method due to improper user input length validation. 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.
wasmtime is a fast and secure runtime for WebAssembly. Rated critical severity (CVSS 9.9), 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.
Heap buffer overflow in Web Audio API in Google Chrome prior to 111.0.5563.64 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap buffer overflow in UMA in Google Chrome prior to 111.0.5563.64 allowed a remote attacker who had compromised the renderer process to potentially exploit heap corruption via a crafted HTML page. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap buffer overflow in Metrics in Google Chrome prior to 111.0.5563.64 allowed a remote attacker who had compromised the renderer process to potentially exploit heap corruption via a crafted HTML. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Stack buffer overflow in Crash reporting in Google Chrome on Windows prior to 111.0.5563.64 allowed a remote attacker who had compromised the renderer process to obtain potentially sensitive. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In apu, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In apu, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In ril, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In display drm, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In widevine, there is a possible out of bounds write due to improper input validation. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In usb, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In usb, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In usb, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In thermal, there is a possible memory corruption due to an uncaught exception. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In pqframework, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In msdc, there is a possible out of bounds write due to an incorrect bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In vow, there is a possible out of bounds write due to an incorrect bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In tinysys, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
A vulnerability in the lsi53c895a device affects the latest version of qemu. Rated medium severity (CVSS 6.0), this vulnerability is low attack complexity.
ISO 15765 and ISO 10681 dissector crash in Wireshark 4.0.0 to 4.0.3 and 3.6.0 to 3.6.11 allows denial of service via packet injection or crafted capture file. Rated high severity (CVSS 7.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability was found in xiaozhuai imageinfo up to 3.0.3. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Out-of-bounds read vulnerability exists in Kostac PLC Programming Software (Former name: Koyo PLC Programming Software) Version 1.6.9.0 and earlier. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Out-of-bounds read vulnerability exists in Kostac PLC Programming Software (Former name: Koyo PLC Programming Software) Version 1.6.9.0 and earlier. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.1376. Rated medium severity (CVSS 6.6), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
OpenZeppelin Contracts is a library for secure smart contract development. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity.
Cubism Core in Live2D Cubism Editor 4.2.03 allows out-of-bounds write via a crafted Section Offset Table or Count Info Table in an MOC3 file. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple vulnerabilities in the web-based management interface of certain Cisco IP Phones could allow an unauthenticated, remote attacker to execute arbitrary code or cause a denial of service (DoS). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Multiple vulnerabilities in the web-based management interface of certain Cisco IP Phones could allow an unauthenticated, remote attacker to execute arbitrary code or cause a denial of service (DoS). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Stack-based buffer overflow vulnerability in the SonicOS allows a remote unauthenticated attacker to cause Denial of Service (DoS), which could cause an impacted firewall to crash. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey1 parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey4_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey2_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wrlEn parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepauth parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the ssid_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the security_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wrlEn_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the ssid parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the security parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepauth_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey3 parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey3_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey1_5g parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey4 parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Jensen of Scandinavia Eagle 1200AC V15.03.06.33_en was discovered to contain a stack overflow via the wepkey2 parameter at /goform/WifiBasicSet. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A heap-based buffer overflow vulnerability exits in GNU LibreDWG v0.12.5 via the bit_read_RC function at bits.c. 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.
Libde265 v1.0.10 was discovered to contain a heap-buffer-overflow vulnerability in the derive_spatial_luma_vector_prediction function in motion.cc. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
There are buffer overflow vulnerabilities in multiple underlying operating system processes that could lead to unauthenticated remote code execution by sending specially crafted packets via the PAPI. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There are buffer overflow vulnerabilities in multiple underlying operating system processes that could lead to unauthenticated remote code execution by sending specially crafted packets via the PAPI. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There are buffer overflow vulnerabilities in multiple underlying operating system processes that could lead to unauthenticated remote code execution by sending specially crafted packets via the PAPI. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There are buffer overflow vulnerabilities in multiple underlying operating system processes that could lead to unauthenticated remote code execution by sending specially crafted packets via the PAPI. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There are buffer overflow vulnerabilities in multiple underlying operating system processes that could lead to unauthenticated remote code execution by sending specially crafted packets via the PAPI. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There are stack-based buffer overflow vulnerabilities that could lead to unauthenticated remote code execution by sending specially crafted packets destined to the PAPI (Aruba Networks access point. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There are stack-based buffer overflow vulnerabilities that could lead to unauthenticated remote code execution by sending specially crafted packets destined to the PAPI (Aruba Networks access point. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
On Feb 15, 2023, the following vulnerability in the ClamAV scanning library was disclosed: A vulnerability in the HFS+ partition file parser of ClamAV versions 1.0.0 and earlier, 0.105.1 and earlier,. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The Sub-IoT implementation of the DASH 7 Alliance protocol has a vulnerability that can lead to an out-of-bounds write prior to implementation version 0.5.0. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
GNU libmicrohttpd before 0.9.76 allows remote DoS (Denial of Service) due to improper parsing of a multipart/form-data boundary in the postprocessor.c MHD_create_post_processor() method. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no authentication required. Public exploit code available.
An out-of-bounds write vulnerability exists in TPM2.0's Module Library allowing writing of a 2-byte data past the end of TPM2.0 command in the CryptParameterDecryption routine. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
An out-of-bounds read vulnerability exists in TPM2.0's Module Library allowing a 2-byte read past the end of a TPM2.0 command in the CryptParameterDecryption routine. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
In dropFramesUntilIframe of AAVCAssembler.cpp, there is a possible out of bounds read due to a heap buffer overflow. Rated high severity (CVSS 7.5), 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.
In phNciNfc_MfCreateXchgDataHdr of phNxpExtns_MifareStd.cpp, there is a possible out of bounds write due to a missing bounds check. 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.
The issue was addressed with improved memory handling. Rated high severity (CVSS 8.6), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A memory corruption issue was addressed with improved state management. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The issue was addressed with improved memory handling. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The issue was addressed with improved memory handling. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A buffer overflow issue was addressed with improved memory handling. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The issue was addressed with improved bounds checks. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
The 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.
An information disclosure issue was addressed by removing the vulnerable code. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Tenda AC500 V2.0.1.9(1307) is vulnerable to Buffer Overflow in function formOneSsidCfgSet via parameter ssid. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Tenda AC500 V2.0.1.9(1307) is vulnerable to Buffer Overflow in function fromAddressNat via parameters entrys and mitInterface. 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.
Tenda AC500 V2.0.1.9(1307) is vulnerable to Buffer Overflow in function fromRouteStatic via parameters entrys and mitInterface. 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.
Tenda Router W30E V1.0.1.25(633) is vulnerable to Buffer Overflow in function fromRouteStatic via parameters entrys and mitInterface. 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.