CVE-2026-56392

GNU coreutils unexpand is vulnerable to a heap-based buffer overflow due to an integer overflow during buffer allocation when processing large tab stop (-t) values. The multiplication used to calculate the allocation size can wrap around, resulting in an undersized buffer. When processing crafted input, subsequent writes exceed the allocated memory, leading to an out‑of‑bounds heap write. When running GNU coreutils unexpand with attacker-provided large tab stop (-t) arguments, this behavior leads to a crash and potentially achieve a heap write primitive depending on memory layout. This issue has been fixed in the commit b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/07/CVE-2026-56391
https://git.savannah.gnu.org/cgit/coreutils.git/
https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d

Configurations

No configuration.

History

24 Jul 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-24 09:16

Updated : 2026-07-30 16:28

NVD link : CVE-2026-56392

Mitre link : CVE-2026-56392

CVE.ORG link : CVE-2026-56392

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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