Integer overflow in Docopt Docopt.cpp

CVE-2025-67125

A signed integer overflow in docopt.cpp v0.6.2 (LeafPattern::match in docopt_private.h) when merging occurrence counters (e.g., default LONG_MAX + first user "-v/--verbose") can cause counter wrap (negative/unbounded semantics) and lead to logic/policy bypass in applications that rely on occurrence-based limits, rate-gating, or safety toggles. In hardened builds (e.g., UBSan or -ftrapv), the overflow may also result in process abort (DoS).

Vulnerability class: Integer Overflow

EPSS: 0.002 (11.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-67125?
CVE-2025-67125 is a medium-severity vulnerability in Docopt Docopt.cpp, classified under Integer Overflow or Wraparound. CVSS score: 4.4/10. Published 2026-01-23.
How severe is CVE-2025-67125?
Medium severity. CVSS v3 base score is 4.4 out of 10.