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 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.
Published: 2026-09-23
Score: 6.5 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-ph9c-7hw9-vhhw JLine: ReDoS in Nano Editor Regex Search Mode
History

Wed, 23 Sep 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 23 Sep 2026 18:30:00 +0000

Type Values Removed Values Added
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 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.
Title JLine: ReDoS in Nano Editor Regex Search Mode
Weaknesses CWE-1333
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-23T19:43:56.607Z

Reserved: 2026-08-20T19:59:59.603Z

Link: CVE-2026-77421

cve-icon Vulnrichment

Updated: 2026-09-23T19:05:08.158Z

cve-icon NVD

Status : Received

Published: 2026-09-23T19:19:15.700

Modified: 2026-09-23T20:17:15.777

Link: CVE-2026-77421

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-23T20:45:09Z

Weaknesses
  • CWE-1333

    Inefficient Regular Expression Complexity