CVE-2026-88355 (GCVE-0-2026-88355)

Vulnerability from cvelistv5 – Published: 2026-09-24 00:00 – Updated: 2026-10-06 17:42
VLAI
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(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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-06 15:44 UTC
CWE
  • n/a
  • CWE-131 - Incorrect Calculation of Buffer Size
Assigner
mitre CNA under the mitre root
CNA scorecard E 28/100 over 2338 records in the last 180 days details
References
Show details on NVD website
To clipboard 

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