CVE catalog
CVE-2026-56741
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
- Severity
- High · CVSS 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.60% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | jline | sid | 1.0-3 | unknown |
| Debian | jline | forky | 1.0-3 | unknown |
| Debian | jline | trixie | 1.0-3 | unknown |
| Debian | jline | bookworm | 1.0-3 | unknown |
| Debian | jline2 | sid | 2.14.6-6 | unknown |
| Debian | jline2 | forky | 2.14.6-6 | unknown |
| Debian | jline2 | trixie | 2.14.6-6 | unknown |
| Debian | jline2 | bookworm | 2.14.6-5 | unknown |
| Debian | jline3 | sid | 3.3.1-5 | vulnerable |
| Debian | jline3 | forky | 3.3.1-5 | vulnerable |
| Debian | jline3 | trixie | 3.3.1-4 | vulnerable |
| Debian | jline3 | bookworm | 3.3.1-3 | vulnerable |
| Cpe | jline | Not reported | Not reported | vulnerable |
| Cpe | jline2 | Not reported | Not reported | vulnerable |
| Cpe | jline3 | Not reported | Not reported | vulnerable |
| Cpe | jline | Not reported | 4.2.1 | fixed |
| Maven | org.jline:jline-remote-telnet | Not reported | 3.30.14 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | jline | source | sid | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline | source | forky | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline | source | trixie | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline2 | source | sid | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline2 | source | forky | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline2 | source | trixie | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline2 | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | jline3 | source | sid | (unfixed) | not yet assigned | Not reported | [1143458] |
| Debian | jline3 | source | forky | (unfixed) | not yet assigned | Not reported | [1143458] |
| Debian | jline3 | source | trixie | (unfixed) | not yet assigned | Not reported | [1143458] |
| Debian | jline3 | source | bookworm | (unfixed) | not yet assigned | Not reported | [1143458] |
| Cpe | jline | cpe | Not reported | 4.2.1 | Not reported | NVD-CVE-2026-56741 | Not reported |
| Maven | org.jline:jline-remote-telnet | maven | Not reported | 3.30.14 | Not reported | GHSA-2R2C-CX56-8933 | Not reported |
Notes
[trixie] jline3: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libjline2-java]Affected
Source package: [jline2]
Details (2)
2.14.6-5· all · bookwormAffected
nvd · jline2 · debian · bookworm; nvd · jline2 · debian · 12
2.14.6-5· all · bookwormAffected
nvd · jline2 · debian · bookworm; nvd · jline2 · debian · 12
- [libjline3-java]Affected
Source package: [jline3]
Details (2)
3.3.1-3· all · bookwormAffected
nvd · jline3 · debian · bookworm; nvd · jline3 · debian · 12
3.3.1-3· all · bookwormAffected
nvd · jline3 · debian · bookworm; nvd · jline3 · debian · 12
- [libjline-java]Affected
Source package: [jline]
Details (2)
1.0-3· all · bookwormAffected
nvd · jline · debian · bookworm; nvd · jline · debian · 12
1.0-3· all · bookwormAffected
nvd · jline · debian · bookworm; nvd · jline · debian · 12
- [libjline-java-doc]Affected
Source package: [jline]
Details (2)
1.0-3· all · bookwormAffected
nvd · jline · debian · bookworm; nvd · jline · debian · 12
1.0-3· all · bookwormAffected
nvd · jline · debian · bookworm; nvd · jline · debian · 12
[Debian 13 (Trixie)]
- [libjline2-java]Affected
Source package: [jline2]
Details (2)
2.14.6-6· all · trixieAffected
nvd · jline2 · debian · 13
2.14.6-6· all · trixieAffected
nvd · jline2 · debian · 13
- [libjline3-java]Affected
Source package: [jline3]
Details (2)
3.3.1-4· all · trixieAffected
nvd · jline3 · debian · 13
3.3.1-4· all · trixieAffected
nvd · jline3 · debian · 13
- [libjline-java]Affected
Source package: [jline]
Details (2)
1.0-3· all · trixieAffected
nvd · jline · debian · 13
1.0-3· all · trixieAffected
nvd · jline · debian · 13
- [libjline-java-doc]Affected
Source package: [jline]
Details (2)
1.0-3· all · trixieAffected
nvd · jline · debian · 13
1.0-3· all · trixieAffected
nvd · jline · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2026_11338-1.json]
- [https://github.com/advisories/GHSA-2r2c-cx56-8933]
- [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/pull/2000]
- [https://github.com/jline/jline3/releases/tag/4.0.16]
- [https://github.com/jline/jline3/releases/tag/4.2.1]
- [https://github.com/jline/jline3/security/advisories/GHSA-2r2c-cx56-8933]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-56741]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-56741]
- [https://security-tracker.debian.org/tracker/CVE-2026-56741]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56741.json]
[Debian Security Tracker] · [FIRST EPSS] · [GitHub Advisory Database] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]