{"schema":"threatline.record/2","record":{"id":"CVE-2026-112021","aliases":[],"summary":"snac2 before 2.93 Heap-Based Buffer Overflow via JSON Parser _xs_json_load_lexer()","details":"snac2 before 2.93 contains a heap-based buffer overflow vulnerability in _xs_json_load_lexer() that allows unauthenticated remote attackers to corrupt heap memory by sending JSON strings containing a \\u0000 escape. Attackers can send a single crafted application/activity+json POST to activitypub_post_handler(), which parses it before signature checks, overflowing heap allocations and crashing the server.","categories":["Unclassified"],"product":"snac2","vendor":"grunfink","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-112021","source_modified_at":"2026-10-19T16:05:15.544Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"snac2","vendor":"grunfink","versions":[{"version":"0","lessThan":"2.93","status":"affected","versionType":"custom"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-112021","source_modified_at":"2026-10-19T16:05:15.544Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"snac2","ecosystem":null},"version":"2.93","basis":"first unaffected version stated in the CVE record"}],"cvss":8.7,"severity":"High","kev":{"listed":false},"epss":{"probability":0.0067,"percentile":0.51423,"score_date":"2026-10-23"},"published_at":"2026-10-18T11:38:40.652Z","modified_at":"2026-10-19T16:05:15.544Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-112021","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T16:05:15.544Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-112021","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://nullenvk.pl/posts/02-snac2-json","tags":["technical-description"]},{"source":"CVE List","url":"https://gist.github.com/nullenvk/2bf288e2d34cb3d4b7143e61dbf7d90b","tags":["exploit"]},{"source":"CVE List","url":"https://codeberg.org/grunfink/snac2/src/tag/2.92/xs_json.h#L283-L285","tags":["technical-description"]},{"source":"CVE List","url":"https://codeberg.org/grunfink/snac2/commit/ec2c5c2046e0381bc942ec5d0d05ec861fe377e7","tags":["patch"]},{"source":"CVE List","url":"https://codeberg.org/grunfink/snac2/releases/tag/2.93","tags":["release-notes"]},{"source":"CVE List","url":"https://codeberg.org/grunfink/snac2","tags":["product"]},{"source":"CVE List","url":"https://www.vulncheck.com/advisories/snac2-before-2.93-heap-based-buffer-overflow-via-json-parser-xs-json-load-lexer","tags":["third-party-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"poc","automatable":"yes","technical_impact":"partial","assessed_at":"2026-10-19T16:04:19.806894Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-19T16:05:15.544Z","content_hash":"0dd44da7b04957667417559c2f4321f072c9727d6b2292b66f3f1f069f422377"}}