Heap Overflow
A heap overflow occurs when a program writes data beyond the bounds of a buffer allocated in the heap memory region.
How It Works
A heap overflow occurs when a program writes data beyond the bounds of a buffer allocated in the heap memory region. Unlike stack overflows that target the call stack, heap overflows corrupt dynamically allocated memory managed by functions like malloc() or new. When a program allocates heap memory without properly validating input size, an attacker can supply excessive data that spills into adjacent heap chunks, corrupting heap metadata structures or neighboring objects.
Exploitation typically targets heap management metadata (chunk headers containing size and status information) or data in adjacent allocations. Attackers can overwrite function pointers stored in heap objects, C++ vtable pointers, or critical data fields to redirect program execution. Modern heap implementations use inline metadata, making them vulnerable to carefully crafted overflows that manipulate allocation structures to achieve arbitrary write primitives.
The attack difficulty varies by heap implementation. Attackers must understand the specific allocator's layout (glibc malloc, Windows heap, etc.) and often need information leaks to defeat ASLR. Heap feng shui techniques arrange heap allocations in predictable patterns, placing attacker-controlled data adjacent to target objects to maximize exploitation reliability.
Impact
- Arbitrary code execution: Overwrite function pointers or vtables to redirect control flow to attacker-supplied shellcode
- Memory corruption: Corrupt critical data structures, causing crashes or logic manipulation to bypass security checks
- Privilege escalation: Modify authorization flags or user context stored in heap objects
- Information disclosure: Trigger controlled crashes that leak sensitive data through error messages or core dumps
- Heap spray payloads: Combined with other vulnerabilities, create reliable exploitation paths across multiple platforms
Real-World Examples
The WhatsApp video call vulnerability (CVE-2019-11931) exploited a heap overflow in video decoding, allowing remote code execution through a malicious video file without user interaction. Attackers could compromise devices by simply calling targets.
The OpenSSL Heartbleed bug (CVE-2014-0160), while primarily an information disclosure issue, demonstrated heap-related vulnerabilities by allowing attackers to read arbitrary heap memory. Similar heap overflow issues in TLS implementations have enabled complete server compromise.
The sudo heap overflow (CVE-2021-3156) allowed local privilege escalation on Unix systems by overflowing a heap buffer through carefully crafted command-line arguments, giving unprivileged users root access on affected systems.
Mitigation
- Memory-safe languages: Use Rust, Go, or managed languages that eliminate manual memory management vulnerabilities
- Hardened heap allocators: Deploy jemalloc, PartitionAlloc, or Scudo with guard pages and randomization features
- Address Space Layout Randomization (ASLR): Randomize heap base addresses to make exploitation non-deterministic
- Bounds checking: Validate all input sizes before heap operations and use safe string functions (
strncpy,snprintf) - Heap integrity checks: Enable heap consistency verification in production environments
- Compiler mitigations: Use AddressSanitizer during development and fortify source options at compile time
- Size limits: Enforce maximum allocation sizes and reject excessive input
Recent CVEs (1940)
A heap-based overflow vulnerability in GetCorrectDbLanguageTypeEsPKc function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in HWR::EngineCJK::Impl::Construct() in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in LoadEnvironment function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access fault. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in GetCorrectDbLanguageTypeEsPKc() function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in ConstructDictionary function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access fault. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in MHW_RECOG_LIB_INFO function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access fault. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in HWR::EngJudgeModel::Construct() in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access fault. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in MHW_RECOG_LIB_INFO function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access fault. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in prepareRecogLibrary function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access fault. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based overflow vulnerability in PrepareRecogLibrary_Part function in libSDKRecognitionText.spensdk.samsung.so library prior to SMR Sep-2022 Release 1 allows attacker to cause memory access. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based buffer overflow flaw was found in the Fribidi package and affects the fribidi_cap_rtl_to_unicode() function of the fribidi-char-sets-cap-rtl.c file. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
A Heap-based Buffer Overflow vulnerability in the SonicWall SMA100 appliance allows a remote authenticated attacker to cause Denial of Service (DoS) on the appliance or potentially lead to code. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A heap-based buffer overflow was found in the Linux kernel's LightNVM subsystem. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity.
A heap-based buffer overflow vulnerability exists in the gif2h5 functionality of HDF5 Group libhdf5 1.10.4. Rated high severity (CVSS 7.8), this vulnerability is 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 9.0.0220. 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 9.0.0211. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Adobe FrameMaker versions 2019 Update 8 (and earlier) and 2020 Update 4 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Adobe FrameMaker versions 2019 Update 8 (and earlier) and 2020 Update 4 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.0102. 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 9.0.0101. 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 9.0.0061. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Adobe InCopy versions 17.2 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe InCopy versions 17.2 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe InDesign versions 17.2.1 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe InDesign versions 17.2.1 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe Character Animator version 4.4.7 (and earlier) and 22.4 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
A vulnerability has been identified in SIMATIC CP 1242-7 V2 (All versions < V3.3.46), SIMATIC CP 1243-1 (All versions < V3.3.46), SIMATIC CP 1243-7 LTE EU (All versions < V3.3.46), SIMATIC CP 1243-7. Rated critical severity (CVSS 10.0), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 9.0.0045. 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 9.0.0044. 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. 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. 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 8.2. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
In multiple CODESYS products, a low privileged remote attacker may craft a request, which may cause a heap-based buffer overflow, resulting in a denial-of-service condition or memory overwrite. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 8.2. 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 8.2. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Adobe InCopy versions 17.2 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe InCopy versions 17.2 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe InDesign versions 17.2.1 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Adobe InDesign versions 17.2.1 (and earlier) and 16.4.1 (and earlier) are affected by a Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of the. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Heap-based Buffer Overflow in GitHub repository hpjansson/chafa prior to 1.12.0. Rated low severity (CVSS 3.3), this vulnerability is low attack complexity. Public exploit code available.
The affected product is vulnerable to a heap-based buffer overflow via uninitialized pointer, which may allow an attacker to execute arbitrary code. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Sofia-SIP is an open-source Session Initiation Protocol (SIP) User-Agent library. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 8.2. 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 8.2. 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 8.2.4968. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available.
Acrobat Reader DC versions 22.001.20085 (and earlier), 20.005.3031x (and earlier) and 17.012.30205 (and earlier) is affected by a heap-based buffer overflow vulnerability due to insecure handling of. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Heap buffer overflow in vim_strncpy find_word in GitHub repository vim/vim prior to 8.2.4919. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in function cmdline_erase_chars in GitHub repository vim/vim prior to 8.2.4899. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
A vulnerability in the handler for HTTP authentication for resources accessed through the Clientless SSL VPN portal of Cisco Adaptive Security Appliance (ASA) Software could allow an authenticated,. Rated high severity (CVSS 7.1), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Heap-based Buffer Overflow in GitHub repository radareorg/radare2 prior to 5.7.0. Rated high severity (CVSS 7.1), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository radareorg/radare2 prior to 5.6.8. Rated medium severity (CVSS 6.1), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
global heap buffer overflow in skip_range in GitHub repository vim/vim prior to 8.2.4763. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
An Uncontrolled Memory Allocation vulnerability leading to a Heap-based Buffer Overflow in the packet forwarding engine (PFE) of Juniper Networks Junos OS allows a network-based unauthenticated. 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.
The affected product is vulnerable to a heap-based buffer overflow, which may lead to code execution. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Heap-based buffer overflow vulnerability in parser_ipma function of libsimba library prior to SMR Apr-2022 Release 1 allows code execution by remote attackers. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow vulnerability in sheifd_get_info_image function in libsimba library prior to SMR Apr-2022 Release 1 allows code execution by remote attacker. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow vulnerability in parser_single_iref function in libsimba library prior to SMR Apr-2022 Release 1 allows code execution by remote attacker. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow vulnerability in parser_infe function in libsimba library prior to SMR Apr-2022 Release 1 allows code execution by remote attacker. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow vulnerability in parser_iloc function in libsimba library prior to SMR Apr-2022 Release 1 allows code execution by remote attacker. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow vulnerability in sheifd_create function of libsimba library prior to SMR Apr-2022 Release 1 allows code execution by remote attackers. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Improper boundary check in Quram Agif library prior to SMR Apr-2022 Release 1 allows arbitrary code execution. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
heap-buffer-overflow in mrb_vm_exec in mruby/mruby in GitHub repository mruby/mruby prior to 3.2. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository strukturag/libde265 prior to and including 1.0.8. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Heap buffer overflow in libr/bin/format/mach0/mach0.c in GitHub repository radareorg/radare2 prior to 5.8.6. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
heap-buffer-overflow in GitHub repository radareorg/radare2 prior to 5.6.8. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
yajl-ruby is a C binding to the YAJL JSON parsing and generation library. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
heap buffer overflow in get_one_sourceline in GitHub repository vim/vim prior to 8.2.4647. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Heap Buffer Overflow in iterate_chained_fixups in GitHub repository radareorg/radare2 prior to 5.6.6. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. Public exploit code available.
Heap Buffer Overflow in parseDragons in GitHub repository radareorg/radare2 prior to 5.6.8. 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 occurs in vim in GitHub repository vim/vim prior to 8.2.4563. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available.
Adobe After Effects versions 22.2 (and earlier) and 18.4.4 (and earlier) are affected by an Heap-based Buffer Overflow vulnerability that could result in arbitrary code execution in the context of. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Heap-based Buffer Overflow in GitHub repository vim/vim prior to 8.2.4436. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository radareorg/radare2 prior to 5.6.4. Rated high severity (CVSS 7.1), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Heap-based Buffer Overflow in GitHub repository radareorg/radare2 prior to 5.6.4. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
MariaDB CONNECT Storage Engine Heap-based Buffer Overflow Privilege Escalation Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Heap-based Buffer Overflow in Homebrew mruby prior to 3.2. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
mruby is vulnerable to Heap-based Buffer Overflow. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Fuji Electric V-Server Lite and Tellus Lite V-Simulator prior to v4.0.12.0 is vulnerable a heap-based buffer overflow when parsing a specially crafted project file, which may allow an attacker to. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
vim is vulnerable to Heap-based Buffer Overflow. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
A vulnerability has been identified in JT Utilities (All versions < V13.1.1.0), JTTK (All versions < V11.1.1.0). 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 JT Utilities (All versions < V13.1.1.0), JTTK (All versions < V11.1.1.0). Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A Heap-based buffer overflow vulnerability in SonicWall SMA100 getBookmarks method allows a remote authenticated attacker to potentially execute code as the nobody user in the appliance. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A missing bounds check in image blurring code prior to WhatsApp for Android v2.21.22.7 and WhatsApp Business for Android v2.21.22.7 could have allowed an out-of-bounds write if a user sent a. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
vim is vulnerable to Heap-based Buffer Overflow. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
vim is vulnerable to Heap-based Buffer Overflow. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
vim is vulnerable to Heap-based Buffer Overflow. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
vim is vulnerable to Heap-based Buffer Overflow. Rated high severity (CVSS 8.0), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
AMD System Management Unit (SMU) may experience a heap-based overflow which may result in a loss of resources. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Zydis is an x86/x86-64 disassembler library. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. Public exploit code available.
vim is vulnerable to Heap-based Buffer Overflow. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.