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CVE-2026-56392

Estado: AnalizadaBaja (1.8)—

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

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

GNU — Coreutils

CWE

Referencias

JSON original (NVD)

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  "published": "2026-07-24T09:16:25.147",
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      "value": "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.\nWhen processing crafted input, subsequent writes exceed the allocated memory, leading to an out‑of‑bounds heap write.\n\nWhen 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.\n\n\n\n\n\n\n\n\n\n\nThis issue has been fixed in the commit b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d"
    }
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  "lastModified": "2026-10-02T13:57:53.010",
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