Upstream information

CVE-2026-56741 at MITRE

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.

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having important severity.

CVSS v3 Scores
CVSS detail CNA (GitHub) SUSE
Base Score 7.5 7.5
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network Network
Attack Complexity Low Low
Privileges Required None None
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact None None
Integrity Impact None None
Availability Impact High High
CVSSv3 Version 3.1 3.1
SUSE Bugzilla entry: 1271948 [NEW]

No SUSE Security Announcements cross referenced.


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Server 16.0 jline3 Already fixed
SUSE Linux Enterprise Server 16.1 jline3 Released
SUSE Linux Enterprise Server for SAP applications 16.0 jline3 Already fixed
SUSE Linux Enterprise Server for SAP applications 16.1 jline3 Released
openSUSE Leap 16.0 jline3 Already fixed


SUSE Timeline for this CVE

CVE page created: Tue Jul 21 11:35:36 2026
CVE page last modified: Wed Jul 22 12:34:32 2026