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 (36536)
NVIDIA DGX Station A100 and DGX Station A800 SBIOS contains a vulnerability where a user may cause a heap-based buffer overflow by local access. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
NVIDIA DGX A100 BMC contains a vulnerability in the host KVM daemon, where an unauthenticated attacker may cause a stack overflow by sending a specially crafted network packet. Rated critical severity (CVSS 9.3), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
NVIDIA DGX A100 baseboard management controller (BMC) contains a vulnerability in the host KVM daemon, where an unauthenticated attacker may cause a stack overflow by sending a specially crafted. Rated critical severity (CVSS 9.3), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
NVIDIA DGX A100 BMC contains a vulnerability in the host KVM daemon, where an unauthenticated attacker may cause stack memory corruption by sending a specially crafted network packet. Rated critical severity (CVSS 9.0), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
The authentication mechanism can be bypassed by overflowing the value of the Cookie "authentication" field, provided there is an active user session. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
uev (aka libuev) before 2.4.1 has a buffer overflow in epoll_wait if maxevents is a large number. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
An out-of-bounds access vulnerability involving netfilter was reported and fixed as: f1082dd31fe4 (netfilter: nf_tables: Reject tables of unsupported family); While creating a new netfilter table,. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
In libebml before 1.4.5, an integer overflow in MemIOCallback.cpp can occur when reading or writing. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in Hancom HCell on Windows allows Overflow Buffers.0.0.893. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Heap-based Buffer Overflow vulnerability in the Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, network based attacker to cause a Denial. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to cause a Denial of Service (DoS). Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
An Out-of-bounds Write vulnerability in J-Web of Juniper Networks Junos OS on SRX Series and EX Series allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS), or Remote. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and EPSS exploitation probability 25.0%.
Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability. Rated medium severity (CVSS 5.2), this vulnerability is no authentication required.
In exiftags 1.01, nikon_prop1 in nikon.c has a heap-based buffer overflow (write of size 28) because snprintf can write to an unexpected address. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A denial service vulnerability has been found on Hex Workshop affecting version 6.7, an attacker could send a command line file arguments and control the Structured Exception Handler (SEH) records. Rated high severity (CVSS 7.3), this vulnerability is low attack complexity. No vendor patch available.
SWFTools 0.9.2 772e55a allows attackers to trigger a large memory-allocation attempt via a crafted document, as demonstrated by pdf2swf. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and 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.
Multiple memory corruption issues were addressed with improved input validation. 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 input validation. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An out-of-bounds read was addressed with improved input validation. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A memory corruption issue was addressed by removing the vulnerable code. Rated high severity (CVSS 7.1), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
The issue was addressed with improved bounds checks. Rated high severity (CVSS 7.1), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A buffer overflow was addressed with improved bounds checking. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
An out-of-bounds write issue was addressed with improved input validation. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
An integer overflow was addressed through 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 memory handling. 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.
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.
Hyland Perceptive Filters releases before 2023-12-08 (e.g., 11.4.0.2647), as used in Cisco IronPort Email Security Appliance Software, Cisco Secure Email Gateway, and various non-Cisco products,. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.mode parameter in the function formSetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.city.vlan parameter in the function getIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stballvlans parameter in the function getIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.port parameter in the function getIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.mode parameter in the function setIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stbpvid parameter in the function setIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.port parameter in the function setIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.city.vlan parameter in the function setIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.city.vlan parameter in the function formGetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stbpvid parameter in the function formGetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.port parameter in the function formGetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.mode parameter in the function formGetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.city.vlan parameter in the function formSetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stballvlans parameter in the function formSetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.port parameter in the function formSetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the iptv.stb.mode parameter in the function formSetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stbpvid parameter in the function formSetIptv. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stballvlans parameter in the function setIptvInfo. 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 AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stballvlans parameter in the function formGetIptv. 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.
Adobe Substance 3D Stager versions 2.1.3 and earlier are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity.
Adobe Substance 3D Stager versions 2.1.3 and earlier are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity.
Adobe Substance 3D Stager versions 2.1.3 and earlier are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity.
Adobe Substance 3D Stager versions 2.1.3 and earlier are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity.
Adobe Substance 3D Stager versions 2.1.3 and earlier are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity.
Adobe Substance 3D Stager versions 2.1.3 and earlier are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity.
Tenda AX1803 v1.0.0.1 contains a stack overflow via the adv.iptv.stbpvid parameter in the function getIptvInfo. 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 vulnerability allows an unauthenticated remote attacker to perform a Denial-of-Service (DoS) attack or, possibly, obtain Remote Code Execution (RCE) via a crafted network request. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
The vulnerability allows an unauthenticated remote attacker to perform a Denial-of-Service (DoS) attack or, possibly, obtain Remote Code Execution (RCE) via a crafted network request. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
The vulnerability allows an unauthenticated remote attacker to perform a Denial-of-Service (DoS) attack or, possibly, obtain Remote Code Execution (RCE) via a crafted network request. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
The vulnerability allows an unauthenticated remote attacker to perform a Denial-of-Service (DoS) attack or, possibly, obtain Remote Code Execution (RCE) via a crafted network request. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
The vulnerability allows an unauthenticated remote attacker to perform a Denial-of-Service (DoS) attack or, possibly, obtain Remote Code Execution (RCE) via a crafted network request. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
Buffer Overflow vulnerability in Tenda AX12 V22.03.01.46, allows remote attackers to cause a denial of service (DoS) via list parameter in SetNetControlList function. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Memory Allocation with Excessive Size Value discovered in BitmapAccess.cpp::FreeImage_AllocateBitmap in FreeImage 3.18.0 allows attackers to cause a denial of service. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A Buffer out-of-bound read vulnerability in Exif.cpp::ReadInt32 in FreeImage 3.18.0 allows attackers to cause a denial-of-service. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
AMI’s SPx contains a vulnerability in the BMC where an Attacker may cause a stack-based buffer overflow via an adjacent network. Rated critical severity (CVSS 9.6), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
AMI’s SPx contains a vulnerability in the BMC where an Attacker may cause a heap memory corruption via an adjacent network. Rated high severity (CVSS 8.3), this vulnerability is no authentication required. No vendor patch available.
AMI’s SPx contains a vulnerability in the BMC where an Attacker may cause a stack memory corruption via an adjacent network. Rated high severity (CVSS 8.3), this vulnerability is no authentication required. No vendor patch available.
AMI’s SPx contains a vulnerability in the BMC where an Attacker may cause a heap memory corruption via an adjacent network. Rated high severity (CVSS 8.3), this vulnerability is no authentication required. No vendor patch available.
AMI’s SPx contains a vulnerability in the BMC where an Attacker may cause a heap memory corruption via an adjacent network. Rated high severity (CVSS 8.3), this vulnerability is no authentication required. No vendor patch available.
AMI’s SPx contains a vulnerability in the BMC where an Attacker may cause a stack-based buffer overflow via an adjacent network. Rated critical severity (CVSS 9.6), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Microsoft Message Queuing Information Disclosure Vulnerability. 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.
Windows Cryptographic Services Information Disclosure Vulnerability. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Windows libarchive Remote Code Execution Vulnerability. Rated high severity (CVSS 7.3), this vulnerability is low attack complexity. Epss exploitation probability 49.4%.
Windows libarchive Remote Code Execution Vulnerability. Rated high severity (CVSS 7.3), this vulnerability is low attack complexity.
Windows Themes Information Disclosure Vulnerability. Rated medium severity (CVSS 4.7). This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Microsoft AllJoyn API Denial of Service Vulnerability. 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.
A security vulnerability exists in FBX that could lead to remote code execution. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Microsoft Message Queuing Information Disclosure Vulnerability. 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.
Microsoft Virtual Hard Disk Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Microsoft Common Log File System Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
A vulnerability was found in Totolink X2000R 1.0.0-B20221212.1452. Rated high severity (CVSS 7.2), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
EDK2 is susceptible to a vulnerability in the CreateHob() function, allowing a user to trigger a integer overflow to buffer overflow via a local network. Rated high severity (CVSS 7.0). No vendor patch available.
EDK2 is susceptible to a vulnerability in the Tcg2MeasurePeImage() function, allowing a user to trigger a heap buffer overflow via a local network. Rated high severity (CVSS 7.0). No vendor patch available.
EDK2 is susceptible to a vulnerability in the Tcg2MeasureGptTable() function, allowing a user to trigger a heap buffer overflow via a local network. Rated high severity (CVSS 7.0). No vendor patch available.
A buffer overflow vulnerability in TA for Linux and TA for MacOS prior to 5.8.1 allows a local user to gain elevated permissions, or cause a Denial of Service (DoS), through exploiting a memory. Rated high severity (CVSS 8.2), this vulnerability is low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
A vulnerability was found in Totolink T6 4.1.9cu.5241_B20210923. 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 vulnerability has been identified in JT2Go (All versions < V14.3.0.6), Teamcenter Visualization V13.3 (All versions < V13.3.0.13), Teamcenter Visualization V14.1 (All versions < V14.1.0.12),. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in JT2Go (All versions < V14.3.0.6), Teamcenter Visualization V13.3 (All versions < V13.3.0.13), Teamcenter Visualization V14.1 (All versions < V14.1.0.12),. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in JT2Go (All versions < V14.3.0.6), Teamcenter Visualization V13.3 (All versions < V13.3.0.13), Teamcenter Visualization V14.1 (All versions < V14.1.0.12),. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in Solid Edge SE2023 (All versions < V223.0 Update 10). Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in Solid Edge SE2023 (All versions < V223.0 Update 10). Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.