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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.002 (13.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Docopt Docopt.cpp — versions 0.6.2
Weakness classification (CWE)
References
- gist.github.com/thesmartshadow/672afe8828844c833f46f8ebe2f5f3bd (Exploit, Third Party Advisory)
- github.com/docopt/docopt.cpp (Product)
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.