Detections
Analytics
CVE-2026-56741
high
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.
References
https://github.com/jline/jline3/security/advisories/GHSA-2r2c-cx56-8933
https://github.com/jline/jline3/releases/tag/4.2.1
https://github.com/jline/jline3/releases/tag/4.0.16
https://github.com/jline/jline3/pull/2000
https://github.com/jline/jline3/commit/86b7ba7801988aadb1a67555629522a71d603bd3
https://github.com/jline/jline3/commit/733eb353dca7b0ea0252e724445b6defa29c393e
https://github.com/jline/jline3/commit/3ea9cad8699714dc072fade29d36be0d1e23d708