CVE-2026-77421

MEDIUM 6.5

JLine: ReDoS in Nano Editor Regex Search Mode

CVSS Score

6.5

EPSS Score

0.0%

EPSS Percentile

0th

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 nano editor's regex search mode passes a user-controlled search term from doSearch(String text) in builtins/src/main/java/org/jline/builtins/Nano.java to Java's backtracking regular expression engine without a timeout or backtracking bound. A nested-quantifier expression evaluated against non-matching buffer content can consume excessive CPU and indefinitely block the editor session thread, and remote multi-user deployments can lose a worker thread for each affected session. This issue is fixed in versions 3.30.15 and 4.3.1.

CWE	CWE-1333
Vendor	jline
Product	jline3
Published	Sep 23, 2026

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CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

jline / jline3

>= 3.0.0, < 3.30.15 >= 4.0.0, < 4.3.1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/jline/jline3/security/advisories/GHSA-ph9c-7hw9-vhhw github.com: https://github.com/jline/jline3/pull/2012 github.com: https://github.com/jline/jline3/pull/2018 github.com: https://github.com/jline/jline3/commit/1d5fc3099e77938b971e197211cad2d4fbb17541 github.com: https://github.com/jline/jline3/commit/341ee69ccc57b7733c1b40d6993219b64b3206ae github.com: https://github.com/jline/jline3/releases/tag/4.3.1 github.com: https://github.com/jline/jline3/releases/tag/jline-3.30.15