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)
In gnss service, 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 connectivity system driver, 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 bluetooth driver, there is a possible out of bounds read due to improper input validation. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In wlan service, there is a possible out of bounds read due to improper input validation. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In wlan driver, 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 power, there is a possible out of bounds write due to an insecure default value. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. No vendor patch available.
In stc, there is a possible out of bounds read due to a race condition. Rated medium severity (CVSS 6.3). No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds write due to a missing valid range checking. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
In imgsys, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
In imgsys_cmdq, there is a possible out of bounds write due to a missing valid range checking. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. No vendor patch available.
In imgsys, there is a possible out of bounds write due to a missing valid range checking. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. No vendor patch available.
In imgsys, there is a possible out of bounds read and write due to a missing valid range checking. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. No vendor patch available.
In imgsys, there is a possible out of bounds read due to a missing valid range checking. Rated medium severity (CVSS 4.2), this vulnerability is low attack complexity. No vendor patch available.
In imgsys, there is a possible out of bounds read due to a race condition. Rated medium severity (CVSS 4.0). No vendor patch available.
In seninf, 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 camsys, 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 gps, 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 gps, 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 gps, 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 gps, 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 gps, 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 ims service, there is a possible memory corruption due to a race condition. Rated medium severity (CVSS 6.4). No vendor patch available.
In cmdq, there is a possible out of bounds read due to an incorrect status check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In netdagent, 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 nvram, 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 wcn bsp driver, there is a possible out of bounds write due to a missing bounds check.This could lead to local denial of service with no additional execution privileges. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
In gnss service, 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 urild service, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
In urild service, there is a possible out of bounds write due to a missing bounds check. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
A vulnerability was found in Tenda AC8 16.03.34.06_cn_TDC01. 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.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.1331. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.1848. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Out-of-bounds Write in GitHub repository vim/vim prior to 9.0.1847. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Integer Overflow or Wraparound in GitHub repository vim/vim prior to 9.0.1846. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
In a typical Virtual Machine Monitor (VMM) there are several components, such as boot loader, virtual device drivers, virtio backend drivers and vhost drivers, that need to access the VM physical. Rated medium severity (CVSS 4.7), this vulnerability is no authentication required. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Integer Overflow or Wraparound in GitHub repository gpac/gpac prior to 2.3-DEV. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Out-of-bounds Read in GitHub repository gpac/gpac prior to 2.3-DEV. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Buffer Overflow vulnerability in hzeller timg v.1.5.1 and before allows a remote attacker to cause a denial of service via the 0x61200000045c address. 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.
Buffer Overflow vulnerability in NETGEAR R6400v2 before version 1.0.4.118, allows remote unauthenticated attackers to execute arbitrary code via crafted URL to httpd. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. 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.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. 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.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. 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.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. 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.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. 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.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. 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.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository gpac/gpac prior to 2.3-DEV. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
In Brocade Fabric OS before v9.2.0a, a local authenticated privileged user can trigger a buffer overflow condition, leading to a kernel panic with large input to buffers in the portcfgfportbuffers. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via the function "sub_7D858.". Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via the function "initIpAddrInfo." In the function, it reads in a user-provided parameter, and the variable is. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via function 'sub_34FD0.' In the function, it reads user provided parameters and passes variables to the function. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via function 'formWifiBasicSet.'. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via function "sub_73004.". Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tengda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via function "R7WebsSecurityHandler.". Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via function "add_white_node,". Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC6 US_AC6V1.0BR_V15.03.05.16_multi_TD01.bin is vulnerable to Buffer Overflow via function "fromGetWirelessRepeat.". Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Tenda AC9 V3.0 V15.03.06.42_multi and Tenda AC5 US_AC5V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter mac at url /goform/GetParentControlInfo. 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 AC7 V1.0 V15.03.06.44, Tenda AC9 V3.0 V15.03.06.42_multi, and Tenda AC5 US_AC5V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter time at url /goform/PowerSaveSet. 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 AC9 V3.0 V15.03.06.42_multi and Tenda AC5 US_AC5V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter startIp and endIp at url /goform/SetPptpServerCfg. 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 AC9 V3.0 V15.03.06.42_multi was discovered to contain a stack overflow via parameter firewallEn at url /goform/SetFirewallCfg. 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 AC7 V1.0 V15.03.06.44, Tenda AC9 V3.0 V15.03.06.42_multi, and Tenda AC5 V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter page at url /goform/NatStaticSetting. 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 AC7 V1.0 V15.03.06.44 was discovered to contain a stack overflow via parameter timeZone at url /goform/SetSysTimeCfg. 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 AC7 V1.0 V15.03.06.44 and Tenda AC5 V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter entrys and mitInterface at url /goform/addressNat. 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 AC7 V1.0 V15.03.06.44, Tenda AC9 V3.0 V15.03.06.42_multi, and Tenda AC5 V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter list at url /goform/SetIpMacBind. 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 AC7 V1.0 V15.03.06.44 was discovered to contain a stack overflow via parameter security_5g at url /goform/WifiBasicSet. 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 AC9 V3.0 V15.03.06.42_multi was discovered to contain a stack overflow via parameter wpapsk_crypto at url /goform/WifiExtraSet. 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 AC9 V3.0 V15.03.06.42_multi and Tenda AC5 US_AC5V1.0RTL_V15.03.06.28 were discovered to contain a stack overflow via parameter list at url /goform/SetStaticRouteCfg. 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 AC7 V1.0 V15.03.06.44 and Tenda AC9 V3.0 V15.03.06.42_multi were discovered to contain a stack overflow via parameter ssid at url /goform/fast_setting_wifi_set. 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 qdrant v.1.3.2 allows a remote attacker cause a denial of service via the chucnked_vectors.rs component. 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.
A memory corruption vulnerability in ArubaOS-Switch could lead to unauthenticated remote code execution by receiving specially crafted packets. 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 exists in the lookup_sequence function of ZBar 0.23.90. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A heap-based buffer overflow exists in the qr_reader_match_centers function of ZBar 0.23.90. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
On affected platforms running Arista EOS with mirroring to multiple destinations configured, an internal system error may trigger a kernel panic and cause system reload. 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.
AOMedia v3.0.0 to v3.5.0 was discovered to contain an invalid read memory access via the component assign_frame_buffer_p in av1/common/av1_common_int.h. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Buffer Overflow vulnerability could allow attackers to corrupt memory to execute arbitrary code or crash the application.
Xmlsoft Libxml2 v2.11.0 was discovered to contain an out-of-bounds read via the xmlSAX2StartElement() function at /libxml2/SAX2.c. 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.
On affected platforms running Arista EOS with VXLAN configured, malformed or truncated packets received over a VXLAN tunnel and forwarded in hardware can cause egress ports to be unable to forward. Rated medium severity (CVSS 6.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An issue was discovered in FRRouting FRR 9.0. 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 issue was discovered in FRRouting FRR through 9.0. Rated critical severity (CVSS 9.1), 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.
An issue was discovered in FRRouting FRR through 9.0. Rated critical severity (CVSS 9.1), 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.