A AegiFlow
HIGHCVSS 7.5EPSS 0.6%

CVE-2026-56740

CVE-2026-56740 updated by NVD

Published
2026-06-18
Modified
2026-10-26
EPSS percentile
46%
Sources
github-advisory, nvd

Summary

JLine is a Java library for handling console input. Prior to 3.30.14, 4.0.16, and 4.2.1, the JLine3 Telnet server remote-telnet module does not limit the number of environment variables a client may inject via the Telnet NEW-ENVIRON option, and TelnetIO.readNEVariables() in TelnetIO.java:1127-1180 stores each variable pair in a HashMap held by ConnectionData, allowing an unauthenticated attacker to flood unique variable pairs before the terminating IAC SE byte and exhaust JVM heap memory with an OutOfMemoryError. This issue is fixed in versions 3.30.14, 4.0.16, and 4.2.1.

Affected packages

EcosystemPackageAffected versionsFixed versions
Mavenorg.jline:jline-remote-telnet—4.2.1, 4.0.16, 3.30.14

Remediation: Upgrade to 4.2.1 or later.

References

Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

CVE® is a registered trademark of The MITRE Corporation. CVE content reproduced under the CVE Terms of Use; copyright designation © MITRE.

EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.