CVE-2026-53910

NVD	https://nvd.nist.gov/vuln/detail/CVE-2026-53910
CWE	https://cwe.mitre.org/data/definitions/190.html

diff3 tool from GNU diffutils is vulnerable to a heap‑based buffer overflow due to multiple signed integer overflows in line‑mapping calculations. Incorrect arithmetic in mapping line ranges can result in corrupted values being used for memory allocation and loop bounds. When processing crafted diff output, these overflows may cause the application to allocate insufficient memory and subsequently perform out‑of‑bounds writes during internal processing. An attacker who can control the output of the diff program used by diff3 (e.g. via –diff-program pointing to a malicious script) can trigger out-of-bounds writes, resulting in a crash and potentially remote code execution depending on the environment.

This issue has been fixed in commit 9ff04d5b84743e331e80b589335a52c5480d1815

Weakness

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

Potential Mitigations

Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
If possible, choose a language or compiler that performs automatic bounds checking.
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
Use libraries or frameworks that make it easier to handle numbers without unexpected consequences.
Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++). [REF-106]
Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.
Use unsigned integers where possible. This makes it easier to perform validation for integer overflows. When signed integers are required, ensure that the range check includes minimum values as well as maximum values.
Understand the programming language’s underlying representation and how it interacts with numeric calculation (CWE-681). Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, “not-a-number” calculations, and how the language handles numbers that are too large or too small for its underlying representation. [REF-7]
Also be careful to account for 32-bit, 64-bit, and other potential differences that may affect the numeric representation.

https://cwe.mitre.org/data/definitions/92.html

Integer Overflow or Wraparound

Weakness

Potential Mitigations

References

CVE-2026-53910

Integer Overflow or Wraparound

Weakness

Potential Mitigations

Related Attack Patterns

References