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{"bugzilla": {"description": "coreutils: GNU coreutils unexpand: Denial of Service via crafted tab stop values", "id": "2506694", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2506694"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L", "status": "draft"}, "cwe": "CWE-787", "details": ["A flaw was found in GNU coreutils, specifically in the `unexpand` utility. This vulnerability, a heap-based buffer overflow, occurs due to an integer overflow when `unexpand` processes unusually large tab stop values provided by a local attacker. This can lead to an undersized memory buffer, allowing subsequent operations to write beyond its boundaries. Successful exploitation can cause the `unexpand` utility to crash, potentially resulting in a denial of service or enabling further memory manipulation."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}, "name": "CVE-2026-56392", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "coreutils", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "coreutils", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "coreutils", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "coreutils", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "coreutils", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "coreutils", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Under investigation", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-07-24T07:44:54Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-56392\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-56392\nhttps://cert.pl/en/posts/2026/07/CVE-2026-56391\nhttps://git.savannah.gnu.org/cgit/coreutils.git/\nhttps://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=b60a159fdc5bfcf9988d3a4cb6f53abe8ad5d35d"], "statement": "A Moderate impact heap-based buffer overflow flaw was found in the `unexpand` utility of GNU coreutils. This vulnerability arises from an integer overflow when processing unusually large tab stop values, leading to an undersized buffer. A local attacker could exploit this by providing crafted input, causing the utility to crash and potentially leading to a denial of service or arbitrary memory manipulation.", "threat_severity": "Moderate"}

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