CVE-2026-56391 (GCVE-0-2026-56391)
Vulnerability from cvelistv5
Published
2026-07-24 07:44
Modified
2026-07-24 12:31
CWE
Summary
GNU coreutils uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input. When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure. This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.
Impacted products
Vendor Product Version
GNU coreutils Version: 9.5   <
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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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