HIGHVulnerability

CVE-2026-56740

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.

Properties

severity
HIGH
score
7.5
cve_id
CVE-2026-56740
vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
published_at
2026-07-17T22:17:57.153
last_modified
2026-08-18T15:23:04.283

Related Entities (3)

HAS_WEAKNESS (1)

[Weakness]Uncontrolled Resource Consumption

DESCRIBED_BY (1)

[Source]NVD

AFFECTS_PRODUCT (1)

[Product]

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CVE-2026-56740 — Ninja Signal Threat Intelligence | Ninja Signal