Description
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).
Scores
CVSS v3
4.4
EPSS
0.0001
EPSS Percentile
0.7%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-190
Status
published
Products (1)
docopt/docopt.cpp
0.6.2
Published
Jan 23, 2026
Tracked Since
Feb 18, 2026