CVE-2026-56740 (GCVE-0-2026-56740)
Vulnerability from cvelistv5
Published
2026-07-17 21:17
Modified
2026-07-20 13:58
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-400 - Uncontrolled Resource Consumption
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.
References
Impacted products
Vendor Product Version
jline jline3 Version: < 3.30.14
Version: >= 4.0.0, < 4.0.16
Version: >= 4.1.0, < 4.2.1
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