{"cvss":7.5,"datePublished":"2026-07-17T22:17:57.317","dateUpdated":"2026-10-24T20:10:00.137","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.","id":"CVE-2026-56741","raw":{"affected":[{"affectedData":[{"product":"jline3","vendor":"jline","versions":[{"status":"affected","version":"< 3.30.14"},{"status":"affected","version":">= 4.0.0, < 4.0.16"},{"status":"affected","version":">= 4.1.0, < 4.2.1"}]}],"source":"security-advisories@github.com"}],"configurations":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:jline:jline:*:*:*:*:*:*:*:*","matchCriteriaId":"7B951CA3-5A41-4A71-9C90-8377E53EC47A","versionEndExcluding":"3.30.14","vulnerable":true},{"criteria":"cpe:2.3:a:jline:jline:*:*:*:*:*:*:*:*","matchCriteriaId":"0949B9BC-A091-477A-B578-92C86B0E5DE8","versionEndExcluding":"4.0.16","versionStartIncluding":"4.0.0","vulnerable":true},{"criteria":"cpe:2.3:a:jline:jline:*:*:*:*:*:*:*:*","matchCriteriaId":"6431F876-039C-4BE1-ABE0-4BFCC22B6F49","versionEndExcluding":"4.2.1","versionStartIncluding":"4.1.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"cveTags":[],"descriptions":[{"lang":"en","value":"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."},{"lang":"es","value":"JLine es una biblioteca Java para manejar la entrada de consola. Antes de las versiones 3.30.14, 4.0.16 y 4.2.1, el módulo remote-telnet del servidor Telnet de JLine3 no aplica un límite superior a las dimensiones del terminal recibidas a través de la opción Telnet NAWS, y TelnetIO.handleNAWS() en TelnetIO.java:856-879 lee el ancho y alto proporcionados por el cliente como enteros sin signo de 16 bits y pasa valores como 65535x65535 a setTerminalGeometry(), permitiendo a un atacante remoto no autenticado alternar repetidamente los valores y desencadenar un trabajo de renderizado costoso y continuo que causa el agotamiento de la CPU y la denegación de servicio. Este problema se ha solucionado en las versiones 3.30.14, 4.0.16 y 4.2.1."}],"id":"CVE-2026-56741","lastModified":"2026-10-24T20:10:00.137","metrics":{"cvssMetricV31":[{"cvssData":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"exploitabilityScore":3.9,"impactScore":3.6,"source":"security-advisories@github.com","type":"Secondary"}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"id":"CVE-2026-56741","options":[{"exploitation":"poc"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-07-20T15:21:00.621662Z","version":"2.0.3"}}]},"published":"2026-07-17T22:17:57.317","references":[{"source":"security-advisories@github.com","tags":["Patch"],"url":"https://github.com/jline/jline3/commit/3ea9cad8699714dc072fade29d36be0d1e23d708"},{"source":"security-advisories@github.com","tags":["Patch"],"url":"https://github.com/jline/jline3/commit/733eb353dca7b0ea0252e724445b6defa29c393e"},{"source":"security-advisories@github.com","tags":["Patch"],"url":"https://github.com/jline/jline3/commit/86b7ba7801988aadb1a67555629522a71d603bd3"},{"source":"security-advisories@github.com","tags":["Issue Tracking"],"url":"https://github.com/jline/jline3/pull/2000"},{"source":"security-advisories@github.com","tags":["Release Notes"],"url":"https://github.com/jline/jline3/releases/tag/4.0.16"},{"source":"security-advisories@github.com","tags":["Release Notes"],"url":"https://github.com/jline/jline3/releases/tag/4.2.1"},{"source":"security-advisories@github.com","tags":["Vendor Advisory","Exploit"],"url":"https://github.com/jline/jline3/security/advisories/GHSA-2r2c-cx56-8933"},{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","tags":["Vendor Advisory","Exploit"],"url":"https://github.com/jline/jline3/security/advisories/GHSA-2r2c-cx56-8933"}],"sourceIdentifier":"security-advisories@github.com","vulnStatus":"Analyzed","weaknesses":[{"description":[{"lang":"en","value":"CWE-400"}],"source":"security-advisories@github.com","type":"Secondary"}]},"severity":"HIGH","source":"nvd","title":"JLine is a Java library for handling console input"}