{"cve":"CVE-2026-56740","nvd":{"published":"2026-07-17T22:17:57.153","modified":"2026-10-24T20:10:00.137","status":"Analyzed","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400"],"references":["https://github.com/jline/jline3/commit/0389f0ee6d0375901b602671ad5dafd4d1d4ee09","https://github.com/jline/jline3/commit/4ee3a73849ffb9a85ec748e4e8cd8f6d81f84f40","https://github.com/jline/jline3/commit/934f09e6128cee33c2b13d42b6e859c1ee2d194b","https://github.com/jline/jline3/pull/2000","https://github.com/jline/jline3/pull/2001"],"products":["jline:jline"],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-56740","score":0.00884,"percentile":0.58958,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-47qp-hqvx-6r3f","url":"https://osv.dev/vulnerability/GHSA-47qp-hqvx-6r3f","summary":"JLine3 Telnet server: Unauthenticated Remote Memory Exhaustion via Unbounded Telnet NEW-ENVIRON Variables","modified":"2026-09-10T03:51:07.920015178Z","packages":[{"ecosystem":"Maven","name":"org.jline:jline-remote-telnet","purl":"pkg:maven/org.jline/jline-remote-telnet","ranges":[">=4.1.0 <4.2.1"],"fixed":["4.2.1"]},{"ecosystem":"Maven","name":"org.jline:jline-remote-telnet","purl":"pkg:maven/org.jline/jline-remote-telnet","ranges":[">=4.0.0 <4.0.16"],"fixed":["4.0.16"]},{"ecosystem":"Maven","name":"org.jline:jline-remote-telnet","purl":"pkg:maven/org.jline/jline-remote-telnet","ranges":["<3.30.14"],"fixed":["3.30.14"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}