CVE-2025-30211 HIGH

CVE-2025-30211: KEX init error results with excessive memory usage

Vendor Erlang
Product otp
Weakness CWE-789
Published March 28, 2025
Last update November 3, 2025

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

Erlang/OTP is a set of libraries for the Erlang programming language. Prior to versions OTP-27.3.1, 26.2.5.10, and 25.3.2.19, a maliciously formed KEX init message can result with high memory usage. Implementation does not verify RFC specified limits on algorithm names (64 characters) provided in KEX init message. Big KEX init packet may lead to inefficient processing of the error data. As a result, large amount of memory will be allocated for processing malicious data. Versions OTP-27.3.1, OTP-26.2.5.10, and OTP-25.3.2.19 fix the issue. Some workarounds are available. One may set option `parallel_login` to `false` and/or reduce the `max_sessions` option.

Key dates

02Disclosure timeline

March 28, 2025 CVE published
November 3, 2025 Record updated