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 (36392)
Memory safety vulnerability leading to memory corruption and Denial of Service in NetScaler ADC and Gateway if the appliance must be configured as a Gateway (VPN Vserver) with RDP Feature enabled OR. Rated high severity (CVSS 8.4), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Illustrator versions 28.7.1 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. No vendor patch available.
Illustrator versions 28.7.1 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. No vendor patch available.
Illustrator versions 28.7.1 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. No vendor patch available.
Illustrator versions 28.7.1 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. No vendor patch available.
Illustrator versions 28.7.1 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Illustrator versions 28.7.1 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Illustrator versions 28.7.1 and earlier are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Audition versions 23.6.9, 24.4.6 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. No vendor patch available.
After Effects versions 23.6.9, 24.6.2 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. No vendor patch available.
After Effects versions 23.6.9, 24.6.2 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. No vendor patch available.
After Effects versions 23.6.9, 24.6.2 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. No vendor patch available.
After Effects versions 23.6.9, 24.6.2 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
After Effects versions 23.6.9, 24.6.2 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
After Effects versions 23.6.9, 24.6.2 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Bridge versions 13.0.9, 14.1.2 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. No vendor patch available.
Illustrator versions 28.7.1 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A heap-based buffer overflow in Fortinet FortiAnalyzer version 7.4.0 through 7.4.2, 7.2.0 through 7.2.5, 7.0.0 through 7.0.12, 6.4.0 through 6.4.14, FortiManager version 7.4.0 through 7.4.2, 7.2.0. Rated high severity (CVSS 7.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A stack-based buffer overflow vulnerability [CWE-121] in Fortinet FortiManager version 7.4.0 through 7.4.2 and before 7.2.5, FortiAnalyzer version 7.4.0 through 7.4.2 and before 7.2.5 and. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
Microsoft Office Graphics Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Microsoft Excel Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Microsoft Excel Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is 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.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows Client-Side Caching 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.
Windows USB Video Class System Driver Elevation of Privilege Vulnerability. Rated medium severity (CVSS 6.8), this vulnerability is 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.
Windows USB Video Class System Driver Elevation of Privilege Vulnerability. Rated medium severity (CVSS 6.8), this vulnerability is 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.
Windows USB Video Class System Driver Elevation of Privilege Vulnerability. Rated medium severity (CVSS 6.8), this vulnerability is 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.
Windows USB Video Class System Driver Elevation of Privilege Vulnerability. Rated medium severity (CVSS 6.8), this vulnerability is 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.
Windows Kernel Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Telephony Service Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows Telephony Service Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Telephony Service Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows Telephony Service Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows Telephony Service Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
LightGBM Remote Code Execution Vulnerability. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows USB Video Class System Driver Elevation of Privilege Vulnerability. Rated medium severity (CVSS 6.8), this vulnerability is 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.
SQL Server Native Client Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
A buffer over-read in Ivanti Secure Access Client before 22.7R4 allows a local unauthenticated attacker to cause a denial of service. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Animate versions 23.0.7, 24.0.4 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Animate versions 23.0.7, 24.0.4 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. No vendor patch available.
An out-of-bounds read vulnerability in Ivanti Avalanche before 6.4.6 allows a remote unauthenticated attacker to leak sensitive information in memory. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A stack-based buffer overflow in Ivanti Connect Secure before version 22.7R2.3 and Ivanti Policy Secure before version 22.7R1.2 allows a remote authenticated attacker with admin privileges to cause a. Rated medium severity (CVSS 4.9), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A stack-based buffer overflow in IPsec of Ivanti Connect Secure before version 22.7R2.3 allows a remote unauthenticated attacker to cause a denial of service. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A stack-based buffer overflow in Ivanti Connect Secure before version 22.7R2.3 and Ivanti Policy Secure before version 22.7R1.2 allows a remote authenticated attacker with admin privileges to cause a. Rated medium severity (CVSS 4.9), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The hda driver is vulnerable to a buffer over-read from a guest-controlled value. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The NVMe driver function nvme_opc_get_log_page is vulnerable to a buffer over-read from a guest-controlled value. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
APTIOV contains a vulnerability in the BIOS where a user or attacker may cause an improper restriction of operations within the bounds of a memory buffer over the network. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
APTIOV contains a vulnerability in BIOS where an attacker may cause an Improper Restriction of Operations within the Bounds of a Memory Buffer by local. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
A vulnerability has been identified in Solid Edge SE2024 (All versions < V224.0 Update 9). Rated high severity (CVSS 7.3), this vulnerability is no authentication required. No vendor patch available.
A vulnerability has been identified in Solid Edge SE2024 (All versions < V224.0 Update 9). Rated high severity (CVSS 7.3), this vulnerability is no authentication required. No vendor patch available.
A buffer overflow vulnerability in the CGI program in the Zyxel GS1900-48 switch firmware version V2.80(AAHN.1)C0 and earlier could allow an authenticated, LAN-based attacker with administrator. Rated medium severity (CVSS 4.5), this vulnerability is low attack complexity. No vendor patch available.
gio/gsocks4aproxy.c in GNOME GLib before 2.82.1 has an off-by-one error and resultant buffer overflow because SOCKS4_CONN_MSG_LEN is not sufficient for a trailing '\0' character. 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.
SuperScan v4.1 was discovered to contain a buffer overflow via the Hostname/IP parameter. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Driver Booster v10.6 was discovered to contain a buffer overflow via the Host parameter under the Customize proxy module. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
GNOME libsoup before 3.6.1 allows a buffer overflow in applications that perform conversion to UTF-8 in soup_header_parse_param_list_strict. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required. Public exploit code available and no vendor patch available.
The boa httpd of Trendnet TEW-820AP 1.01.B01 has a stack overflow vulnerability in /boafrm/formIPv6Addr, /boafrm/formIpv6Setup, /boafrm/formDnsv6. 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.
If an attacker tricks a valid user into running Delta Electronics DIAScreen with a file containing malicious code, a stack-based buffer overflow in BACnetObjectInfo can be exploited, allowing the. Rated high severity (CVSS 8.4), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
If an attacker tricks a valid user into running Delta Electronics DIAScreen with a file containing malicious code, a stack-based buffer overflow in BACnetParameter can be exploited, allowing the. Rated high severity (CVSS 8.4), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
If an attacker tricks a valid user into running Delta Electronics DIAScreen with a file containing malicious code, a stack-based buffer overflow in CEtherIPTagItem can be exploited, allowing the. Rated high severity (CVSS 8.4), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A vulnerability classified as critical was found in Tenda AC10 16.03.10.13. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
WeeChat before 4.4.2 has an integer overflow and resultant buffer overflow at core/core-string.c when there are more than two billion items in a list. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability, which was classified as critical, was found in Tenda AC10 16.03.10.13. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A vulnerability was found in D-Link DI-8003 16.07.16A1. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A vulnerability was found in D-Link DI-8003 16.07.16A1. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix out-of-bounds write in trie_get_next_key() trie_get_next_key() allocates a node stack with size trie->max_prefixlen, while. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
In the Linux kernel, the following vulnerability has been resolved: netdevsim: Add trailing zero to terminate the string in nsim_nexthop_bucket_activity_write() This was found by a static analyzer. 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.
In the Linux kernel, the following vulnerability has been resolved: bpf: Check the validity of nr_words in bpf_iter_bits_new() Check the validity of nr_words in bpf_iter_bits_new(). Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity.
In the Linux kernel, the following vulnerability has been resolved: ntfs3: Add bounds checking to mi_enum_attr() Added bounds checking to make sure that every attr don't stray beyond valid memory. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. This Buffer Overflow vulnerability could allow attackers to corrupt memory to execute arbitrary code or crash the application.