SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-77420

From 3.0.0 until 3.30.15 and 4.3.1, DefaultHistory.matchPatterns(String patterns, String line) in reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java converts the HISTORY_IGNORE configuration value into a Java regular expression while…

MEDIUM 5.5EPSS 0.18%

Does this matter?

Lower severity and a low EPSS score (0.18%). Track it; it rarely justifies an emergency change on its own.

Description

JLine is a Java library for handling console input. From 3.0.0 until 3.30.15 and 4.3.1, DefaultHistory.matchPatterns(String patterns, String line) in reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java converts the HISTORY_IGNORE configuration value into a Java regular expression while escaping only part of its syntax, allowing other regex metacharacters to reach the backtracking engine. An attacker who can control application or user configuration can supply a nested-quantifier expression that is reevaluated whenever a command is added to history, consuming excessive CPU and indefinitely blocking the reader thread. This issue is fixed in versions 3.30.15 and 4.3.1.

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.18% probability · 8th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-1333
Source
security-advisories@github.com
EPSS trend
0%3%5%24 September 2026: 0.12%26 October 2026: 0.18%24 September 202626 October 2026

EPSS moved from 0.1% on 24 September 2026 to 0.2% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.