High 7.5Published Jul 17, 2026

CVE-2026-56740JLine is a Java library for handling console input.

Updated under an hour ago (2026-10-19 07:00 UTC)

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Every CVE for jline

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-400
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Analyzed
Record last updated: Aug 18, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

jline jline jline:jline	before 3.30.14; from 4.0.0 before 4.0.16; from 4.1.0 before 4.2.1	NVD

References

https://github.com/jline/jline3/commit/0389f0ee6d0375901b602671ad5dafd4d1d4ee09patch
https://github.com/jline/jline3/commit/4ee3a73849ffb9a85ec748e4e8cd8f6d81f84f40patch
https://github.com/jline/jline3/commit/934f09e6128cee33c2b13d42b6e859c1ee2d194bpatch
https://github.com/jline/jline3/pull/2000issue-tracking
https://github.com/jline/jline3/pull/2001issue-tracking
https://github.com/jline/jline3/releases/tag/4.0.16release-notes
https://github.com/jline/jline3/releases/tag/4.2.1release-notes
https://github.com/jline/jline3/releases/tag/jline-3.30.14release-notes
https://github.com/jline/jline3/security/advisories/GHSA-47qp-hqvx-6r3fexploit, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.