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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-56740 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/jline/jline3/commit/0389f0ee6d0375901b602671ad5dafd4d1d4ee09 GitHub, Inc.
https://github.com/jline/jline3/commit/4ee3a73849ffb9a85ec748e4e8cd8f6d81f84f40 GitHub, Inc.
https://github.com/jline/jline3/commit/934f09e6128cee33c2b13d42b6e859c1ee2d194b GitHub, Inc.
https://github.com/jline/jline3/pull/2000 GitHub, Inc.
https://github.com/jline/jline3/pull/2001 GitHub, Inc.
https://github.com/jline/jline3/releases/tag/4.0.16 GitHub, Inc.
https://github.com/jline/jline3/releases/tag/4.2.1 GitHub, Inc.
https://github.com/jline/jline3/releases/tag/jline-3.30.14 GitHub, Inc.
https://github.com/jline/jline3/security/advisories/GHSA-47qp-hqvx-6r3f GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-400 Uncontrolled Resource Consumption GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-56740
NVD Published Date:
07/17/2026
NVD Last Modified:
07/17/2026
Source:
GitHub, Inc.