CVE-2026-56392
LOW
1,8
Source: [email protected]
Attack Vector: local
Attack Complexity: low
Privileges Required: none
User Interaction: active
Confidentiality: N/A
Integrity: N/A
Availability: N/A
Description
AI Translation Available
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
122
Heap-based Buffer Overflow
DraftCommon Consequences
Security Scopes Affected:
Availability
Integrity
Confidentiality
Access Control
Other
Potential Impacts:
Dos: Crash, Exit, Or Restart
Dos: Resource Consumption (Cpu)
Dos: Resource Consumption (Memory)
Execute Unauthorized Code Or Commands
Bypass Protection Mechanism
Modify Memory
Other
Applicable Platforms
Languages:
Memory-Unsafe, C, C++
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=b60a159fdc5bfcf9988d…