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 (3033)
SerialiseValue in RenderDoc before 1.27 allows an Integer Overflow with a resultant Buffer Overflow. 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 was found in libcap. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
A vulnerability was found in ImageMagick. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The `Toybox.Graphics.BufferedBitmap.initialize` API method in CIQ API version 2.3.0 through 4.1.7 does not validate its parameters, which can result in integer overflows when allocating the. 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.
sysstat through 12.7.2 allows a multiplication integer overflow in check_overflow in common.c. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Vyper is a Pythonic smart contract language for the Ethereum virtual machine. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Integer Overflow or Wraparound in GitHub repository vim/vim prior to 9.0.1532. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available.
Windows Kernel 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 iSCSI Target Service Information Disclosure Vulnerability. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
MaraDNS is open-source software that implements the Domain Name System (DNS). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
An integer overflow 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.
RIOT-OS, an operating system that supports Internet of Things devices, contains a network stack with the ability to process 6LoWPAN frames. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
RIOT-OS, an operating system that supports Internet of Things devices, contains a network stack with the ability to process 6LoWPAN frames. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
This vulnerability allows network-adjacent attackers to disclose sensitive information on affected installations of Sonos One Speaker 70.3-35220. Rated medium severity (CVSS 6.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A vulnerability within the Avira network protection feature allowed an attacker with local execution rights to cause an overflow. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Altran picoTCP through 1.7.0 allows memory corruption (and subsequent denial of service) because of an integer overflow in pico_ipv6_alloc when processing large ICMPv6 packets. 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 maliciously crafted X_B file when parsed through Autodesk® AutoCAD® 2023 can be used to cause an Integer Overflow. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Memory Corruption in Multimedia Framework due to integer overflow when synx bind is called along with synx signal. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Adobe Acrobat Reader versions 23.001.20093 (and earlier) and 20.005.30441 (and earlier) are affected by an Integer Underflow or Wraparound vulnerability that could result in arbitrary code execution. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Windows Kernel Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available.
Windows DNS Server Information Disclosure Vulnerability. Rated medium severity (CVSS 4.9), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Kernel Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Pragmatic General Multicast (PGM) Remote Code Execution Vulnerability. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows Kernel 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 Network File System Information Disclosure Vulnerability. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows Kernel Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Microsoft PostScript and PCL6 Class Printer Driver Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity.
Certain Lexmark devices through 2023-02-19 have an Integer Overflow. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In wlan, 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 wlan, 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 wlan, 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 wlan, 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 wlan, there is a possible out of bounds read due to an integer overflow. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
Calling any of the Parse functions on Go source code which contains //line directives with very large line numbers can cause an infinite loop due to integer overflow. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
An issue was discovered in Samsung Exynos Mobile Processor and Baseband Modem Processor for Exynos 1280, Exynos 2200, and Exynos Modem 5300. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Rocket Software UniData versions prior to 8.2.4 build 3003 and UniVerse versions prior to 11.3.5 build 1001 or 12.2.1 build 2002 suffer from a heap-based buffer overflow in the unirpcd daemon that,. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Adobe Dimension versions 3.4.7 (and earlier) is affected by an Integer Overflow or Wraparound vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
A buffer overflow vulnerability was found in the Netfilter subsystem in the Linux Kernel. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
TensorFlow is an open source platform for machine learning. 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.
TensorFlow is an open source platform for machine learning. 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.
In fdt_next_tag of fdt.c, 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.
OpenSIPS is a Session Initiation Protocol (SIP) server implementation. 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.
Microsoft PostScript and PCL6 Class Printer Driver Information Disclosure Vulnerability. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity.
Microsoft PostScript and PCL6 Class Printer Driver Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Remote Procedure Call Runtime Remote Code Execution Vulnerability. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Microsoft PostScript and PCL6 Class Printer Driver Information Disclosure Vulnerability. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Bluetooth Service Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Remote Procedure Call Runtime Remote Code Execution Vulnerability. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Microsoft PostScript and PCL6 Class Printer Driver Elevation of Privilege Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity.
Microsoft PostScript and PCL6 Class Printer Driver Information Disclosure Vulnerability. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Partition Management Driver 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 HTTP.sys Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available.
Remote Procedure Call Runtime Remote Code Execution Vulnerability. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Windows Point-to-Point Protocol over Ethernet (PPPoE) Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.0). This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Remote Procedure Call Runtime Remote Code Execution Vulnerability. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Libelfin v0.3 was discovered to contain an integer overflow in the load function at elf/mmap_loader.cc. 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.
The kernel subsystem function check_permission_for_set_tokenid within OpenHarmony-v3.1.5 and prior versions has an UAF vulnerability which local attackers can exploit this vulnerability to escalate. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In keyinstall, 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.
Redis is an in-memory database that persists on disk. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
The affected products are vulnerable to an integer overflow or wraparound, which could allow an attacker to crash the server and remotely execute arbitrary code. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Integer overflow in PDF in Google Chrome prior to 110.0.5481.177 allowed a remote attacker to potentially exploit heap corruption via a crafted PDF file. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
afu_mmio_region_get_by_offset in drivers/fpga/dfl-afu-region.c in the Linux kernel through 6.1.12 has an integer overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Libpeconv - integer overflow, before commit 75b1565 (30/11/2022). Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Visual Studio Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows iSCSI Discovery Service Remote Code Execution Vulnerability. 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.
Windows Media Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Microsoft ODBC Driver 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.
Microsoft ODBC Driver for SQL Server Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Microsoft Word Remote Code Execution Vulnerability. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Microsoft ODBC Driver for SQL Server Remote Code Execution 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.
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.
Microsoft PostScript and PCL6 Class Printer Driver Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity.
Integer overflow in Core in Google Chrome prior to 110.0.5481.77 allowed a remote attacker who had one a race condition to potentially exploit heap corruption via a crafted HTML page. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
In ged, 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.
A use-after-free flaw was found in io_uring/filetable.c in io_install_fixed_file in the io_uring subcomponent in the Linux Kernel during call cleanup. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
Integer overflow vulnerability in function Q_DecCoordOnUnitSphere file bifs/unquantize.c in GPAC version 2.2-rev0-gab012bbfb-master. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Redis is an in-memory database that persists on disk. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. This Integer Overflow vulnerability could allow attackers to cause unexpected behavior through arithmetic overflow.
Adobe Acrobat Reader versions 22.003.20282 (and earlier), 22.003.20281 (and earlier) and 20.005.30418 (and earlier) are affected by an Integer Overflow or Wraparound vulnerability that could result. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
In rndis_query_oid in drivers/net/wireless/rndis_wlan.c in the Linux kernel through 6.1.5, there is an integer overflow in an addition. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Print Spooler Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Windows Kernel Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Microsoft Cryptographic Services Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
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. No vendor patch available.
Microsoft Cryptographic Services Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
Windows Lightweight Directory Access Protocol (LDAP) Denial of Service Vulnerability. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Windows Layer 2 Tunneling Protocol (L2TP) Remote Code Execution Vulnerability. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
Windows iSCSI Service Denial of Service Vulnerability. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The bzip2 crate before 0.4.4 for Rust allow attackers to cause a denial of service via a large file that triggers an integer overflow in mem.rs. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
NVIDIA GPU Display Driver for Linux contains a vulnerability in the kernel mode layer (nvidia.ko), where an integer overflow may lead to information disclosure or data tampering. Rated high severity (CVSS 7.1), this vulnerability is low attack complexity. No vendor patch available.
NVIDIA GPU Display Driver for Linux contains a vulnerability in the kernel mode layer handler, where an Integer overflow may lead to denial of service or information disclosure. Rated high severity (CVSS 7.1), this vulnerability is low attack complexity. No vendor patch available.