{"api_version":"1","generated_at":"2026-09-24T15:48:44+00:00","cve":"CVE-2026-77420","urls":{"html":"https://cve.report/CVE-2026-77420","api":"https://cve.report/api/cve/CVE-2026-77420.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-77420","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-77420"},"summary":{"title":"JLine: ReDoS via `HISTORY_IGNORE` Configuration Variable","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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-09-23 19:19:15","updated_at":"2026-09-23 19:19:15"},"problem_types":["CWE-1333","CWE-1333 CWE-1333: Inefficient Regular Expression Complexity"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"5.5","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"5.5","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":5.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://github.com/jline/jline3/pull/2012","name":"https://github.com/jline/jline3/pull/2012","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541","name":"https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/jline/jline3/pull/2018","name":"https://github.com/jline/jline3/pull/2018","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae","name":"https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/jline/jline3/releases/tag/4.3.1","name":"https://github.com/jline/jline3/releases/tag/4.3.1","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/jline/jline3/releases/tag/jline-3.30.15","name":"https://github.com/jline/jline3/releases/tag/jline-3.30.15","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/jline/jline3/security/advisories/GHSA-5q95-hrpc-m3w3","name":"https://github.com/jline/jline3/security/advisories/GHSA-5q95-hrpc-m3w3","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-77420","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77420","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"jline","product":"jline3","version":"affected >= 3.0.0, < 3.30.15","platforms":[]},{"source":"CNA","vendor":"jline","product":"jline3","version":"affected >= 4.0.0, < 4.3.1","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"jline3","vendor":"jline","versions":[{"status":"affected","version":">= 3.0.0, < 3.30.15"},{"status":"affected","version":">= 4.0.0, < 4.3.1"}]}],"descriptions":[{"lang":"en","value":"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."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":5.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1333","description":"CWE-1333: Inefficient Regular Expression Complexity","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-23T18:11:25.998Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/jline/jline3/security/advisories/GHSA-5q95-hrpc-m3w3","tags":["x_refsource_CONFIRM"],"url":"https://github.com/jline/jline3/security/advisories/GHSA-5q95-hrpc-m3w3"},{"name":"https://github.com/jline/jline3/pull/2012","tags":["x_refsource_MISC"],"url":"https://github.com/jline/jline3/pull/2012"},{"name":"https://github.com/jline/jline3/pull/2018","tags":["x_refsource_MISC"],"url":"https://github.com/jline/jline3/pull/2018"},{"name":"https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541","tags":["x_refsource_MISC"],"url":"https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541"},{"name":"https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae","tags":["x_refsource_MISC"],"url":"https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae"},{"name":"https://github.com/jline/jline3/releases/tag/4.3.1","tags":["x_refsource_MISC"],"url":"https://github.com/jline/jline3/releases/tag/4.3.1"},{"name":"https://github.com/jline/jline3/releases/tag/jline-3.30.15","tags":["x_refsource_MISC"],"url":"https://github.com/jline/jline3/releases/tag/jline-3.30.15"}],"source":{"advisory":"GHSA-5q95-hrpc-m3w3","discovery":"UNKNOWN"},"title":"JLine: ReDoS via `HISTORY_IGNORE` Configuration Variable"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-77420","datePublished":"2026-09-23T18:11:25.998Z","dateReserved":"2026-08-20T19:59:59.603Z","dateUpdated":"2026-09-23T18:11:25.998Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-23 19:19:15","lastModifiedDate":"2026-09-23 19:19:15","problem_types":["CWE-1333","CWE-1333 CWE-1333: Inefficient Regular Expression Complexity"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"77420","Ordinal":"1","Title":"JLine: ReDoS via `HISTORY_IGNORE` Configuration Variable","CVE":"CVE-2026-77420","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"77420","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"JLine: ReDoS via `HISTORY_IGNORE` Configuration Variable"}]}}}