Integer Overflow
Integer overflow occurs when an arithmetic operation produces a result that exceeds the maximum value a given integer type can store.
How It Works
Integer overflow occurs when an arithmetic operation produces a result that exceeds the maximum value a given integer type can store. In C/C++, this causes the value to "wrap around" to a small number—for example, if a 32-bit unsigned integer at maximum value (4,294,967,295) has 1 added, it wraps to 0. Attackers exploit this by providing carefully crafted input values that, when used in calculations, produce unexpectedly small results.
The most dangerous scenario involves memory allocation. An attacker supplies large values that overflow during size calculations (often when adding header sizes, element counts, or alignment padding), producing a small allocation size. When the program later writes the originally intended large amount of data into this undersized buffer, a heap overflow occurs. For instance: size = user_count * sizeof(struct) + header might overflow if user_count is sufficiently large, resulting in malloc() allocating a tiny buffer that subsequent operations overflow.
Integer overflows also enable logic bypasses. Length checks can be circumvented when overflowed values appear to pass validation. Loop bounds may become incorrect, causing excessive iterations or premature termination. Signed integer overflow (technically undefined behavior in C/C++) can flip positive values to negative, bypassing security checks that assume non-negative numbers.
Impact
- Heap buffer overflow: Undersized allocations lead to memory corruption, enabling arbitrary code execution
- Authentication bypass: Overflowed counters or size checks may skip security validations
- Denial of service: Invalid memory operations cause crashes or infinite loops
- Information disclosure: Incorrect bounds allow reading beyond intended memory regions
- Privilege escalation: Combined with memory corruption, can compromise system integrity
Real-World Examples
The OpenSSH authentication bypass (CVE-2002-0639) involved an integer overflow in challenge-response handling where the number of responses could overflow, allowing authentication bypass. The overflow caused allocation of insufficient memory, which subsequent code exploited to execute arbitrary code.
ImageMagick suffered multiple integer overflow vulnerabilities (CVE-2016-3714 and related) where maliciously crafted image files with extreme dimension values caused size calculations to overflow. This resulted in small heap allocations followed by large writes, enabling remote code execution through image processing.
The Linux kernel's do_brk() function (CVE-2003-0961) contained an integer overflow when calculating memory region sizes. Attackers could wrap the size value to bypass length checks and map memory at arbitrary locations, achieving local privilege escalation.
Mitigation
- Safe arithmetic libraries: Use compiler intrinsics (
__builtin_add_overflow) or libraries (SafeInt, Rust's checked arithmetic) that detect overflow - Pre-calculation validation: Check that operands won't overflow before performing arithmetic operations
- Compiler protections: Enable
-ftrapv(GCC) or/RTCc(MSVC) to trap signed overflow; use UBSan for detection - Use larger types: Perform calculations in 64-bit integers when operands are 32-bit, verify result fits before casting down
- Input validation: Enforce maximum reasonable values on user input before arithmetic
- Modern languages: Use languages with overflow checking (Rust, Swift) or arbitrary precision integers (Python, Java BigInteger)
Recent CVEs (3031)
Microsoft WDAC OLE DB provider for SQL Server Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
In ged, there is a possible out of bounds write due to an integer overflow. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
in OpenHarmony v4.0.0 and prior versions allow a local attacker cause heap overflow through integer overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
in OpenHarmony v4.0.0 and prior versions allow a local attacker cause heap overflow through integer overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A buffer overflow was found in Shim in the 32-bit system. Rated high severity (CVSS 7.4), this vulnerability is no authentication required. No vendor patch available.
Integer overflow vulnerability in FFmpeg before n6.1, allows attackers to cause a denial of service (DoS) via the avcodec/osq module. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Integer overflow vulnerability in FFmpeg before n6.1, allows remote attackers to execute arbitrary code via the JJPEG XL Parser. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Integer overflow vulnerability in FFmpeg before n6.1, allows remote attackers to execute arbitrary code via the jpegxl_anim_read_packet component in the JPEG XL Animation decoder. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Integer Overflow or Wraparound vulnerability in Linux Linux kernel kernel on Linux, x86, ARM (md, raid, raid5 modules) allows Forced Integer Overflow. Rated medium severity (CVSS 4.4), this vulnerability is remotely exploitable. No vendor patch available.
copy_params in drivers/md/dm-ioctl.c in the Linux kernel through 6.7.1 can attempt to allocate more than INT_MAX bytes, and crash, because of a missing param_kernel->data_size check. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
An out-of-bounds memory read flaw was found in receive_encrypted_standard in fs/smb/client/smb2ops.c in the SMB Client sub-component in the Linux Kernel. Rated high severity (CVSS 7.4), this vulnerability is low attack complexity.
NVIDIA DGX A100 SBIOS contains a vulnerability where a local attacker can cause input validation checks to be bypassed by causing an integer overflow. Rated medium severity (CVSS 6.6). No vendor patch available.
The authentication mechanism can be bypassed by overflowing the value of the Cookie "authentication" field, provided there is an active user session. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In libebml before 1.4.5, an integer overflow in MemIOCallback.cpp can occur when reading or writing. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
An integer overflow was addressed through improved input validation. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Redis is an in-memory database that persists on disk. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
An integer overflow vulnerability in Exif.cpp::jpeg_read_exif_dir in FreeImage 3.18.0 allows attackers to obtain information and cause a denial of service. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
An integer overflow vulnerability in LoadPixelDataRLE4 function in PluginBMP.cpp in Freeimage 3.18.0 allows attackers to obtain sensitive information, cause a denial of service and/or run arbitrary. 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.
An integer overflow vulnerability in FreeImageIO.cpp::_MemoryReadProc in FreeImage 3.18.0 allows attackers to obtain sensitive information, cause a denial-of-service attacks and/or run arbitrary code. 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.
Windows Kernel-Mode Driver Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Kernel Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Epss exploitation probability 21.7%.
Microsoft ODBC Driver Remote Code Execution Vulnerability. Rated high severity (CVSS 8.0), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Multiple integer underflow vulnerabilities exist in the LXT2 lxt2_rd_iter_radix shift operation functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Multiple integer underflow vulnerabilities exist in the LXT2 lxt2_rd_iter_radix shift operation functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 num_dict_entries functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 num_dict_entries functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the LXT2 facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT vzt_rd_block_vch_decode dict parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT vzt_rd_block_vch_decode dict parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT vzt_rd_block_vch_decode times parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT vzt_rd_block_vch_decode times parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the VZT facgeometry parsing functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the FST fstReaderIterBlocks2 chain_table allocation functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Multiple integer overflow vulnerabilities exist in the FST fstReaderIterBlocks2 chain_table allocation functionality of GTKWave 3.3.115. 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 integer overflow vulnerability exists in the fstReaderIterBlocks2 temp_signal_value_buf allocation functionality of GTKWave 3.3.115. 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 integer overflow vulnerability exists in the FST fstReaderIterBlocks2 vesc allocation functionality of GTKWave 3.3.115, when compiled as a 32-bit binary. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
An integer overflow vulnerability exists in the LXT2 zlib block allocation functionality of GTKWave 3.3.115. 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 integer overflow vulnerability exists in the fstReaderIterBlocks2 time_table tsec_nitems functionality of GTKWave 3.3.115. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
An integer overflow vulnerability exists in the LXT2 lxt2_rd_trace value elements allocation functionality of GTKWave 3.3.115. 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 integer overflow vulnerability exists in the VZT longest_len value allocation functionality of GTKWave 3.3.115. 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 integer overflow vulnerability exists in the FST_BL_GEOM parsing maxhandle functionality of GTKWave 3.3.115, when compiled as a 32-bit binary. Rated high severity (CVSS 7.0), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
CommonMarker versions prior to 0.23.4 are at risk of an integer overflow vulnerability. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Memory corruption while receiving a message in Bus Socket Transport Server. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
Memory corruption in TZ Secure OS while requesting a memory allocation from TA region. Rated critical severity (CVSS 9.3), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
In battery, there is a possible information disclosure due to an integer overflow. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
An issue was discovered in the HTTP2 implementation in Qt before 5.15.17, 6.x before 6.2.11, 6.3.x through 6.5.x before 6.5.4, and 6.6.x before 6.6.2. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Matrix SSL 4.x through 4.6.0 and Rambus TLS Toolkit have a length-subtraction integer overflow for Client Hello Pre-Shared Key extension parsing in the TLS 1.3 server. 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.
ClickHouse® is an open-source column-oriented database management system that allows generating analytical data reports in real-time. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Apache Guacamole 1.5.3 and older do not consistently ensure that values received from a VNC server will not result in integer overflow. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
PlutoSVG commit 336c02997277a1888e6ccbbbe674551a0582e5c4 and before was discovered to contain an integer overflow via the component plutosvg_load_from_memory. 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 flaw was found in xorg-server. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Sysmain Service Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
A flaw was found in PostgreSQL that allows authenticated database users to execute arbitrary code through missing overflow checks during SQL array value modification. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
In gpu_pixel_handle_buffer_liveness_update_ioctl of private/google-modules/gpu/mali_kbase/mali_kbase_core_linux.c, there is a possible out of bounds write due to an integer overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
An integer underflow vulnerability exists in the NTRIP Stream Parsing functionality of GPSd 3.25.1~dev. 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.
Integer overflow vulnerability in landmarkCopyImageToNative of libFacePreProcessingjni.camera.samsung.so prior to SMR Dec-2023 Release 1 allows attacker to trigger heap overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Integer overflow vulnerability in detectionFindFaceSupportMultiInstance of libFacePreProcessingjni.camera.samsung.so prior to SMR Dec-2023 Release 1 allows attacker to trigger heap overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Transient DOS in Bluetooth Host while rfc slot allocation. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
An integer overflow vulnerability in the source code of the QuickSec IPSec toolkit used in the VPN feature of the Zyxel ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An malicious BLE device can cause buffer overflow by sending malformed advertising packet BLE device using Zephyr OS, leading to DoS or potential RCE on the victim BLE device. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Vim is an open source command line text editor. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Vim is an open source command line text editor. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Vim is an open source command line text editor. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Vim is an open source command line text editor. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Vim is an open source command line text editor. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Microsoft Remote Registry Service Remote Code Execution Vulnerability. Rated high severity (CVSS 7.2), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Deployment Services Denial of Service Vulnerability. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
A local non-privileged user can make improper GPU memory processing operations to gain access to already freed memory. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Videolan VLC prior to version 3.0.20 contains an Integer underflow that leads to an incorrect packet length. 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.
Memory corruption in Audio while processing the VOC packet data from ADSP. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Ppmd7.c in 7-Zip before 23.00 allows an integer underflow and invalid read operation via a crafted 7Z archive. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Integer overflow in USB in Google Chrome prior to 119.0.6045.105 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In Sysproxy, there is a possible out of bounds write due to an integer underflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In Secure Element, there is a possible out of bounds write due to an integer overflow. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
In the Security Element API, there is a possible out of bounds write due to an integer overflow. Rated medium severity (CVSS 6.7), this vulnerability is low attack complexity. No vendor patch available.
Vim is an improved version of the good old UNIX editor Vi. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. Public exploit code available.
An issue in OpenImageIO oiio v.2.4.12.0 allows a remote attacker to execute arbitrary code and cause a denial of service via the read_rle_image function of file bifs/unquantize.c. 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.
An integer overflow exists in the "HyperLinkFrame" stream parser of Ichitaro 2023 1.0.1.59372. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
zchunk before 1.3.2 has multiple integer overflows via malformed zchunk files to lib/comp/comp.c, lib/comp/zstd/zstd.c, lib/dl/multipart.c, or lib/header.c. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.