{"id":"CVE-2026-88355","title":"An incorrect buffer size calculation vulnerability exists in tinyexpr commit 4a7456e in new_expr()","summary":"An incorrect buffer size calculation vulnerability exists in tinyexpr commit 4a7456e in new_expr(). For arity-0 expression nodes, including constants, variables, and zero-argument functions, the function allocates less memory than sizeof…","severity":"none","published":"2026-09-24","updated":"2026-09-24","sourceUpdated":"2026-09-24T21:08:55.030","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-88355","references":[{"url":"https://github.com/codeplea/tinyexpr/issues/145","label":"cve@mitre.org"},{"url":"https://github.com/szaydel/tinyexpr/commit/fe7459728c2ab8d2f91365abe56601cdd0e24f9b","label":"cve@mitre.org"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-24T15:45:56.663Z","slug":"CVE-2026-88355","body":"## Overview\n\nAn incorrect buffer size calculation vulnerability exists in tinyexpr commit 4a7456e in new_expr(). For arity-0 expression nodes, including constants, variables, and zero-argument functions, the function allocates less memory than sizeof(te_expr) but treats the returned allocation as a complete te_expr object. This results in undefined behavior and can cause deterministic process termination in UBSan-instrumented builds.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}