Resource Exhaustion Affecting jline3 package, versions *


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.88% (58th percentile)

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  • Snyk IDSNYK-ECHOLATEST-JLINE3-18011556
  • published18 Jul 2026
  • disclosed17 Jul 2026

Introduced: 17 Jul 2026

CVE-2026-56740  (opens in a new tab)
CWE-400  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest jline3.

NVD Description

Note: Versions mentioned in the description apply only to the upstream jline3 package and not the jline3 package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1