MitM attack in Erlang OTP SSH

1) Expected behavior violation

EUVDB-ID: #VU108847

Risk: Low

CVSSv4.0: 0.6 [CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-46712

CWE-ID: CWE-440 - Expected Behavior Violation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform MitM attack.

The vulnerability exists due to OTP SSH fails to enforce strict kex handshake hardening measures by allowing optional messages to be exchanged. A remote attacker can perform a Man-in-the-Middle attack and inject these messages in a connection during the handshake.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

otp: 22.0 - 27.3.3

CPE2.3

• cpe:2.3:a:erlang:otp:22.0:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.1:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.4:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.5:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.6:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.0.7:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.1:*:*:*:*:*:*:*
• cpe:2.3:a:erlang:otp:22.1.1:*:*:*:*:*:*:*

External links

https://github.com/erlang/otp/releases/tag/OTP-25.3.2.21
https://github.com/erlang/otp/releases/tag/OTP-26.2.5.12
https://github.com/erlang/otp/releases/tag/OTP-27.3.4
https://github.com/erlang/otp/security/advisories/GHSA-934x-xq38-hhqf

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.