{"cve":"CVE-2026-77420","nvd":{"published":"2026-09-23T19:19:15.510","modified":"2026-09-30T19:38:27.293","status":"Awaiting Analysis","description":"JLine is a Java library for handling console input. From 3.0.0 until 3.30.15 and 4.3.1, DefaultHistory.matchPatterns(String patterns, String line) in reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java converts the HISTORY_IGNORE configuration value into a Java regular expression while escaping only part of its syntax, allowing other regex metacharacters to reach the backtracking engine. An attacker who can control application or user configuration can supply a nested-quantifier expression that is reevaluated whenever a command is added to history, consuming excessive CPU and indefinitely blocking the reader thread. This issue is fixed in versions 3.30.15 and 4.3.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-1333"],"references":["https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541","https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae","https://github.com/jline/jline3/pull/2012","https://github.com/jline/jline3/pull/2018","https://github.com/jline/jline3/releases/tag/4.3.1"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:02.509636177+00:00"},"epss":{"cve":"CVE-2026-77420","score":0.00181,"percentile":0.07634,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-5q95-hrpc-m3w3","url":"https://osv.dev/vulnerability/GHSA-5q95-hrpc-m3w3","summary":"JLine: ReDoS via `HISTORY_IGNORE` Configuration Variable","modified":"2026-09-23T18:15:03.944840213Z","packages":[{"ecosystem":"Maven","name":"org.jline:jline-reader","purl":"pkg:maven/org.jline/jline-reader","ranges":[">=4.0.0 <4.3.1"],"fixed":["4.3.1"]},{"ecosystem":"Maven","name":"org.jline:jline-reader","purl":"pkg:maven/org.jline/jline-reader","ranges":[">=3.0.0 <3.30.15"],"fixed":["3.30.15"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}