{"cve":"CVE-2026-56741","nvd":{"published":"2026-07-17T22:17:57.317","modified":"2026-10-24T20:10:00.137","status":"Analyzed","description":"JLine is a Java library for handling console input. Prior to 3.30.14, 4.0.16, and 4.2.1, the JLine3 Telnet server remote-telnet module does not apply an upper bound to terminal dimensions received via the Telnet NAWS option, and TelnetIO.handleNAWS() in TelnetIO.java:856-879 reads client-supplied width and height as 16-bit unsigned integers and passes values such as 65535x65535 to setTerminalGeometry(), allowing an unauthenticated remote attacker to repeatedly alternate values and trigger continuous expensive rendering work that causes CPU exhaustion and denial of service. This issue is fixed in versions 3.30.14, 4.0.16, and 4.2.1.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400"],"references":["https://github.com/jline/jline3/commit/3ea9cad8699714dc072fade29d36be0d1e23d708","https://github.com/jline/jline3/commit/733eb353dca7b0ea0252e724445b6defa29c393e","https://github.com/jline/jline3/commit/86b7ba7801988aadb1a67555629522a71d603bd3","https://github.com/jline/jline3/pull/2000","https://github.com/jline/jline3/releases/tag/4.0.16"],"products":["jline:jline"],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-56741","score":0.00595,"percentile":0.48158,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-2r2c-cx56-8933","url":"https://osv.dev/vulnerability/GHSA-2r2c-cx56-8933","summary":"JLine3 Telnet server: Unauthenticated Remote DoS via Unbounded Telnet NAWS Terminal Geometry","modified":"2026-09-10T03:51:07.726046123Z","packages":[{"ecosystem":"Maven","name":"org.jline:jline-remote-telnet","purl":"pkg:maven/org.jline/jline-remote-telnet","ranges":[">=4.1.0 <4.2.1"],"fixed":["4.2.1"]},{"ecosystem":"Maven","name":"org.jline:jline-remote-telnet","purl":"pkg:maven/org.jline/jline-remote-telnet","ranges":[">=4.0.0 <4.0.16"],"fixed":["4.0.16"]},{"ecosystem":"Maven","name":"org.jline:jline-remote-telnet","purl":"pkg:maven/org.jline/jline-remote-telnet","ranges":["<3.30.14"],"fixed":["3.30.14"]}]}],"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."]}