JLine up to 3.30.14/4.3.0 History DefaultHistory.java DefaultHistory.matchPatterns patterns resource consumption

Summaryinfo

A vulnerability, which was classified as problematic, was found in JLine up to 3.30.14/4.3.0. This vulnerability affects the function DefaultHistory.matchPatterns of the file reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java of the component History. Such manipulation of the argument patterns leads to resource consumption. This vulnerability is uniquely identified as CVE-2026-77420. Local access is required to approach this attack. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in JLine up to 3.30.14/4.3.0 and classified as problematic. Affected by this issue is the function DefaultHistory.matchPatterns of the file reader/src/main/java/org/jline/reader/impl/history/DefaultHistory.java of the component History. The manipulation of the argument patterns with an unknown input leads to a resource consumption vulnerability. Using CWE to declare the problem leads to CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. Impacted is availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-77420 since 08/20/2026. The exploitation is known to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit.

Upgrading to version 3.30.15 or 4.3.1 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

• JLine

Version

• 3.30.0
• 3.30.1
• 3.30.2
• 3.30.3
• 3.30.4
• 3.30.5
• 3.30.6
• 3.30.7
• 3.30.8
• 3.30.9
• 3.30.10
• 3.30.11
• 3.30.12
• 3.30.13
• 3.30.14
• 4.0
• 4.1
• 4.2
• 4.3.0

CPE 2.3info

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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