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 apply an upper bound to terminal dimensions received via the Telnet NAWS option, and TelnetIO.handleNAWS() in TelnetIO.java:856-879 reads client-supplied width and height as 16-bit unsigned integers and passes values such as 65535x65535 to setTerminalGeometry(), allowing an unauthenticated remote attacker to repeatedly alternate values and trigger continuous expensive rendering work that causes CPU exhaustion and denial of service. This issue is fixed in versions 3.30.14, 4.0.16, and 4.2.1.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| jline | jline3 | < 3.30.14, >= 4.0.0, < 4.0.16, >= 4.1.0, < 4.2.1 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | jline +1 | No fix yet | — |
| Debian 14 | jline3 | 3.29.0+ds-2 | — |
| Debian 13 | jline +2 | No fix yet | — |
| Debian 12 | jline +2 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | jline +2 | No fix yet | — |
| Ubuntu 26.04 LTS | jline +2 | No fix yet | — |
| Ubuntu 24.04 LTS | jline +2 | No fix yet | — |
| Ubuntu 22.04 LTS | jline +2 | No fix yet | — |
| Ubuntu 20.04 LTS | jline +1 | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | jline +1 | No fix yet | — |
| Ubuntu 16.04 LTS | jline +1 | No fix yet | — |
| Ubuntu 14.04 LTS | jline +1 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | jline3 | 3.30.15-160000.1.1 | SUSE-SU-2026:22856-1 |
| SLES 16.0 | jline3 | 3.30.15-160000.1.1 | SUSE-SU-2026:22856-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | jline3 | 3.30.15-3.1 | openSUSE-SU-2026:11338-1 |
| openSUSE Leap 16.0 | jline3 | 3.30.15-160000.1.1 | openSUSE-SU-2026:21423-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | jline | No fix yet | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | apache-nifi-toolkit | 2.10.0-r1 | — |
| Wolfi rolling | apache-pulsar-4.2 | 4.2.2-r4 | — |
| Wolfi rolling | celeborn-0.6 | No fix yet | — |
| Wolfi rolling | confluent-kafka | 8.4.0.269-r1 | — |
| Wolfi rolling | druid | 37.0.0-r14 | — |
| Wolfi rolling | kafka-4.1 | 4.1.2-r3 | — |
| Wolfi rolling | kafka-4.2 | 4.2.1-r3 | — |
| Wolfi rolling | spark-4.0-scala-2.13 | 4.0.4-r6 | — |
| Wolfi rolling | spark-4.1-scala-2.13 | 4.1.3-r5 | — |
| Wolfi rolling | tez | 0.10.5-r19 | — |
| Wolfi rolling | zookeeper-3.9 | 3.9.5-r8 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.jline:jline-remote-telnet | >= 4.1.0, < 4.2.1 | 4.2.1 | GHSA-2r2c-cx56-8933 |
| Maven | org.jline:jline-remote-telnet | >= 4.0.0, < 4.0.16 | 4.0.16 | GHSA-2r2c-cx56-8933 |
| Maven | org.jline:jline-remote-telnet | < 3.30.14 | 3.30.14 | GHSA-2r2c-cx56-8933 |
Advisories 5
- NCSC-2026-0448 Kwetsbaarheden verholpen in Oracle Fusion Middleware NCSC-NL (Netherlands) · Oct 22, 2026
- WID-SEC-2026-4078 Oracle Fusion Middleware: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 20, 2026
- SUSE-SU-2026:22856-1 Security update for jline3 SUSE / openSUSE Security Updates · Jul 28, 2026
- openSUSE-SU-2026:21423-1 Security update for jline3 SUSE / openSUSE Security Updates · Jul 24, 2026
- openSUSE-SU-2026:11338-1 jline3-3.30.15-3.1 on GA media SUSE / openSUSE Security Updates · Jul 23, 2026
References
- https://github.com/jline/jline3/security/advisories/GHSA-2r2c-cx56-8933
- https://github.com/jline/jline3/pull/2000
- https://github.com/jline/jline3/commit/3ea9cad8699714dc072fade29d36be0d1e23d708
- https://github.com/jline/jline3/commit/733eb353dca7b0ea0252e724445b6defa29c393e
- https://github.com/jline/jline3/commit/86b7ba7801988aadb1a67555629522a71d603bd3
- https://github.com/jline/jline3/releases/tag/4.0.16
- https://github.com/jline/jline3/releases/tag/4.2.1