CVE-2026-77423

high

Description

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.

References

https://github.com/jline/jline3/security/advisories/GHSA-2v9w-34q6-wpqx

https://github.com/jline/jline3/releases/tag/jline-3.30.15

https://github.com/jline/jline3/releases/tag/4.3.1

https://github.com/jline/jline3/pull/2018

https://github.com/jline/jline3/pull/2012

https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae

https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541

Details

Source: Mitre, NVD

Published: 2026-09-23

Updated: 2026-09-24

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

EPSS

EPSS: 0.00385