{"id":"UBUNTU-CVE-2026-77423","details":"JLine is a Java library for handling console input. From 3.0.0 until 3.30.15 and 4.3.1, the JLine built-in less viewer passes user-controlled search and display-filter patterns from getPattern(boolean doDisplayPattern) in builtins/src/main/java/org/jline/builtins/Less.java directly to Java's backtracking regular expression engine and repeatedly applies them to file content. A nested-quantifier expression evaluated against non-matching lines can consume excessive CPU and indefinitely block the session thread, and repeated sessions in Telnet or SSH deployments can exhaust a bounded worker pool. This issue is fixed in versions 3.30.15 and 4.3.1.","modified":"2026-09-25T06:36:57.266573001Z","published":"2026-09-24T00:00:00Z","upstream":["CVE-2026-77423"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-77423"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-77423"},{"type":"REPORT","url":"https://github.com/jline/jline3/security/advisories/GHSA-2v9w-34q6-wpqx"},{"type":"REPORT","url":"https://github.com/jline/jline3/pull/2018"},{"type":"REPORT","url":"https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae"},{"type":"REPORT","url":"https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541"},{"type":"REPORT","url":"https://github.com/jline/jline3/pull/2012"},{"type":"REPORT","url":"https://github.com/jline/jline3/releases/tag/4.3.1"},{"type":"REPORT","url":"https://github.com/jline/jline3/releases/tag/jline-3.30.15"}],"affected":[{"package":{"name":"jline","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/jline?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libjline-java","binary_version":"1.0-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline2","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/jline2?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.11-1","2.11-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libjline2-java","binary_version":"2.11-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/jline?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libjline-java","binary_version":"1.0-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline2","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/jline2?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.11-4"],"ecosystem_specific":{"binaries":[{"binary_version":"2.11-4","binary_name":"libjline2-java"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/jline?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0-2"],"ecosystem_specific":{"binaries":[{"binary_version":"1.0-2","binary_name":"libjline-java"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline2","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/jline2?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.11-4","2.12.1-1","2.14.6-1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.14.6-1","binary_name":"libjline2-java"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/jline?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libjline-java","binary_version":"1.0-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline2","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/jline2?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.14.6-3"],"ecosystem_specific":{"binaries":[{"binary_name":"libjline2-java","binary_version":"2.14.6-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/jline?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0-3"],"ecosystem_specific":{"binaries":[{"binary_name":"libjline-java","binary_version":"1.0-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-77423.json"}},{"package":{"name":"jline2","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/jline2?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.14.6-4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