Improper Check for Unusual or Exceptional Conditions vulnerability in the pattern and patternProperties keywords in lud jsv allows an unauthenticated remote attacker to bypass schema validation via a string that matches a schema regex only after heavy backtracking. JSV.Helpers.RegexExt.bounded_match?/2 runs schema regexes with a backtracking budget but calls :re.run/3 without :report_errors, so a match that exhausts the budget returns the same :nomatch as a real non-match. A key that matches a patternProperties regex is then checked against additionalProperties or not at all, and a string that matches a not subschema with a pattern is accepted. Before the budget existed, Regex.match?/2 failed the same way at Erlang's default match limit.
Only schemas whose regex explores a catastrophic branch before the branch that matches are affected. The attacker controls the data, not the schema, and linear patterns never exhaust the budget.
This issue affects jsv: from 0.1.0 before 0.26.2.
CVSS
No CVSS.
References
Configurations
No configuration.
History
02 Nov 2026, 20:17
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://github.com/lud/jsv/security/advisories/GHSA-cvmg-hgv6-jqcp - |
01 Nov 2026, 14:18
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-11-01 14:18
Updated : 2026-11-02 20:17
NVD link : CVE-2026-117680
Mitre link : CVE-2026-117680
CVE.ORG link : CVE-2026-117680
JSON object : View
Products Affected
No product.
CWE
CWE-754
Improper Check for Unusual or Exceptional Conditions