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{"bugzilla": {"description": "bison: GNU Bison: Arbitrary file overwrite via grammar-defined output paths", "id": "2508370", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2508370"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.6", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:L", "status": "draft"}, "cwe": "CWE-22", "details": ["A flaw was found in GNU Bison. When processing attacker-supplied grammar, the software improperly handles grammar-defined output paths. This allows an attacker to use directives such as %output and %header to specify arbitrary file paths. Consequently, generated files can be directed to any writable location on the filesystem, potentially overwriting existing files and leading to data integrity issues."], "name": "CVE-2026-56390", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "bison", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "bison", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Fix deferred", "package_name": "bison", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "bison", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "bison", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-07-29T09:40:03Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-56390\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-56390\nhttps://cert.pl/en/posts/2026/07/CVE-2026-56389\nhttps://cgit.git.savannah.gnu.org/cgit/bison.git/\nhttps://cgit.git.savannah.gnu.org/cgit/bison.git/commit/?id=8d101c19d4d9aaedf83a448c925513742d4efcf0"], "threat_severity": "Moderate"}

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