{"id":"CVE-2026-63209","revision":"b1e6ecec2a4e4a83b603a5e34fecaddb","records":[{"revision":"b1e6ecec2a4e4a83b603a5e34fecaddb","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-63209","aliases":[],"title":"Integer Overflow or Wraparound and Out-of-bounds Write in compress","description":"compress provides various compression algorithms. Prior to version 1.18.7, a signed integer overflow vulnerability in s2.NewDict() allows an attacker to bypass repeat index validation by supplying a dictionary with a uvarint-encoded repeat value exceeding MaxInt64. When Dict.Encode() is subsequently called, the overflowed negative repeat value causes an out-of-bounds memory access via unsafe.Pointer arithmetic, crashing the process with SIGSEGV. This issue has been patched in version 1.18.7.","state":0,"publishedAt":"2026-09-29T14:58:53.366+00:00","modifiedAt":"2026-09-29T16:32:32.677+00:00","affected":[{"ecosystem":"Vendor product","name":"compress","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"klauspost\",\n                    \"product\": \"compress\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 1.18.7\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://github.com/klauspost/compress/security/advisories/GHSA-259r-337f-4rfw","https://github.com/klauspost/compress/commit/539243b8823ee8f03e49969823d57c348c917536","https://github.com/klauspost/compress/releases/tag/v1.18.7"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-63209","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-63209","identifiers":["CVE-2026-63209"]},"retained":false,"historicalAffected":[]}],"coverage":[]}