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 (36711)
A buffer overflow was addressed with improved size validation. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A memory corruption issue was addressed with improved validation. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A memory corruption issue was addressed with improved state management. Rated high severity (CVSS 7.1), this vulnerability is low attack complexity. No vendor patch available.
A memory corruption 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 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.
A memory corruption 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 memory corruption issue was addressed with improved state management. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A memory corruption issue was addressed with improved input validation. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A buffer overflow was addressed with improved size validation. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Multiple memory corruption issues were 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.
Multiple memory corruption issues were 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.
An out-of-bounds read was addressed with improved bounds checking. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
An out-of-bounds read was addressed with improved bounds checking. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Multiple memory corruption issues were 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.
An out-of-bounds read was addressed with improved bounds checking. Rated medium severity (CVSS 6.5), 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 high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
An out-of-bounds read issue existed that led to the disclosure of kernel memory. Rated medium severity (CVSS 5.5), this vulnerability is 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 low attack complexity. No vendor patch available.
Multiple memory corruption issues were addressed with improved input validation. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
A memory corruption issue was addressed with improved memory handling. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
A memory corruption 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.
A memory corruption 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.
Multiple memory corruption issues were 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.
An out-of-bounds read issue existed that led to the disclosure of kernel memory. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Multiple memory corruption issues were 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.
An issue was discovered on TRENDnet TEW-651BR 2.04B1, TEW-652BRP 3.04b01, and TEW-652BRU 1.00b12 devices. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Integer overflow to buffer overflow due to lack of validation of event arguments received from firmware. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Device memory may get corrupted because of buffer overflow/underflow. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Out of boundary access is possible as there is no validation of data accessed against the received size of the packet in case of malicious firmware in Snapdragon Auto, Snapdragon Compute, Snapdragon. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Write vulnerability could allow attackers to write data beyond allocated buffer boundaries leading to code execution or crashes.
Out of bounds memcpy can occur by providing the embedded NULL character string and length greater than the actual string length in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity,. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
Buffer overwrite can occur in IEEE80211 header filling function due to lack of range check of array index received from firmware in Snapdragon Auto, Snapdragon Consumer Electronics Connectivity,. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
Out of bound access can occur while processing peer info in IBSS connection mode due to lack of upper bounds check to ensure that for loop further will not cause an overflow in Snapdragon Auto,. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
Possibility of out of bound access in debug queue, if packet size field is corrupted in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer Electronics Connectivity,. 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.
Improper check in video driver while processing data from video firmware can lead to integer overflow and then buffer overflow in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity,. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Possible OOB issue in EEPROM due to lack of check while accessing memory map array at the time of reading operation in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer Electronics. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Out-of-bound read in the wireless driver in the Linux kernel due to lack of check of buffer length. Rated critical severity (CVSS 9.8), 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.
Improper length check on source buffer to handle userspace data received can lead to out-of-bound access in diag handlers in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer Electronics. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Buffer Overflow vulnerability could allow attackers to corrupt memory to execute arbitrary code or crash the application.
Improper validation of event buffer extracted from FW response can lead to integer overflow, which will allow to pass the length check and eventually will lead to buffer overwrite when event data is. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Buffer overflow during SIB read when network configures complete sib list along with first and last segment of other SIB in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer IOT, Snapdragon. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Multiple read overflows in MM while decoding service accept,service reject,attach reject and MT detach in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer IOT, Snapdragon Industrial IOT,. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
While processing MT Secondary PDP request, Buffer overflow will happen due to incorrect calculation of buffer size in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer IOT, Snapdragon. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Buffer over read can happen while parsing SMS OTA messages at transport layer if network sends un-intended values in Snapdragon Auto, Snapdragon Compute, Snapdragon Consumer IOT, Snapdragon. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Out of bound write can happen in WMI firmware event handler due to lack of validation of data received from WLAN firmware in Snapdragon Auto, Snapdragon Consumer Electronics Connectivity, Snapdragon. 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.
In Advantech DiagAnywhere Server, Versions 3.07.11 and prior, multiple stack-based buffer overflow vulnerabilities exist in the file transfer service listening on the TCP port. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Libspiro through 20190731 has a stack-based buffer overflow in the spiro_to_bpath0() function in spiro.c. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. Public exploit code available and no vendor patch available.
In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image and performing some operations can cause slab-out-of-bounds write access in __btrfs_map_block in fs/btrfs/volumes.c, because a. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
In the Linux kernel 5.0.21, mounting a crafted f2fs filesystem image can cause __remove_dirty_segment slab-out-of-bounds write access because an array is bounded by the number of dirty types (8) but. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The JBIG2Decode library in npdf.dll in Nitro Free PDF Reader 12.0.0.112 has a CAPPDAnnotHandlerUtils::PDAnnotHandlerDestroyData2+0xa08a Out-of-Bounds Read via crafted Unicode content. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
In TensorFlow before 1.15, a heap buffer overflow in UnsortedSegmentSum can be produced when the Index template argument is int32. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Out of bounds write in firmware for Intel(R) NUC(R) may allow a privileged user to potentially enable escalation of privilege via local access. Rated medium severity (CVSS 6.7), 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.
Improper buffer restrictions in firmware for Intel(R) NUC(R) may allow an authenticated user to potentially enable escalation of privilege via local access. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Buffer Overflow vulnerability could allow attackers to corrupt memory to execute arbitrary code or crash the application.
read_colordef in read.c in Xfig fig2dev 3.2.7b has an out-of-bounds write. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Certain Huawei products (AP2000;IPS Module;NGFW Module;NIP6300;NIP6600;NIP6800;S5700;SVN5600;SVN5800;SVN5800-C;SeMG9811;Secospace AntiDDoS8000;Secospace USG6300;Secospace USG6500;Secospace. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Certain Huawei products (AP2000;IPS Module;NGFW Module;NIP6300;NIP6600;NIP6800;S5700;SVN5600;SVN5800;SVN5800-C;SeMG9811;Secospace) have a resource management vulnerability. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Certain Huawei products (AP2000;IPS Module;NGFW Module;NIP6300;NIP6600;NIP6800;S5700;SVN5600;SVN5800;SVN5800-C;SeMG9811;Secospace AntiDDoS8000;Secospace USG6300;Secospace USG6500;Secospace. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Certain Huawei products (AP2000;IPS Module;NGFW Module;NIP6300;NIP6600;NIP6800;S5700;SVN5600;SVN5800;SVN5800-C;SeMG9811;Secospace AntiDDoS8000;Secospace USG6300;Secospace USG6500;Secospace. Rated high severity (CVSS 8.6), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There is an out-of-bounds read vulnerability in the Advanced Packages feature of the Gauss100 OLTP database in CampusInsight before V100R019C00SPC200. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Yabasic 2.86.2 has a heap-based buffer overflow in myformat in function.c via a crafted BASIC source 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.
samurai 0.7 has a heap-based buffer overflow in canonpath in util.c via a crafted build 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.
A stack-based buffer overflow in processCommandUploadSnapshot in libcommon.so in Petwant PF-103 firmware 4.22.2.42 and Petalk AI 3.2.2.30 allows remote attackers to cause denial of service or run. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A stack-based buffer overflow in processCommandUploadLog in libcommon.so in Petwant PF-103 firmware 4.22.2.42 and Petalk AI 3.2.2.30 allows remote attackers to cause denial of service or run. 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.
ATasm 1.06 has a stack-based buffer overflow in the get_signed_expression() function in setparse.c via a crafted .m65 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.
ATasm 1.06 has a stack-based buffer overflow in the parse_expr() function in setparse.c via a crafted .m65 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.
ATasm 1.06 has a stack-based buffer overflow in the to_comma() function in asm.c via a crafted .m65 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.
An issue was discovered in Envoy 1.12.0. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
The FTP client in AceaXe Plus 1.0 allows a buffer overflow via a long EHLO response from an FTP server. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An issue was discovered in libsixel 1.8.2. 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.
stb_image.h (aka the stb image loader) 2.23, as used in libsixel and other products, has a heap-based buffer over-read in stbi__load_main. 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.
Advantech WebAccess before 8.4.3 allows unauthenticated remote attackers to execute arbitrary code or cause a denial of service (memory corruption) due to a stack-based buffer overflow when handling. 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 SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). 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 vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). 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 vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in SPPA-T3000 MS3000 Migration Server (All versions). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been identified in EN100 Ethernet module DNP3 variant (All versions), EN100 Ethernet module IEC 61850 variant (All versions < V4.37), EN100 Ethernet module IEC104 variant (All. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.