| Name | CVE-2026-56740 |
| 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| jline (PTS) | bookworm, forky, bullseye, sid, trixie | 1.0-3 | undetermined |
| jline2 (PTS) | bullseye | 2.14.6-4 | undetermined |
| bookworm | 2.14.6-5 | undetermined | |
| forky, sid, trixie | 2.14.6-6 | undetermined | |
| jline3 (PTS) | bullseye | 3.3.1-2 | vulnerable |
| bookworm | 3.3.1-3 | vulnerable | |
| trixie | 3.3.1-4 | vulnerable | |
| forky, sid | 3.3.1-5 | vulnerable |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| jline | source | (unstable) | undetermined | |||
| jline2 | source | (unstable) | undetermined | |||
| jline3 | source | (unstable) | (unfixed) |
https://github.com/jline/jline3/security/advisories/GHSA-47qp-hqvx-6r3f
https://github.com/jline/jline3/pull/2000
Fixed by: https://github.com/jline/jline3/commit/4ee3a73849ffb9a85ec748e4e8cd8f6d81f84f40 (jline-3.30.14)