CVE-2025-32433
Erlang Erlang/OTP SSH Server Missing Authentication for Critical Function Vulnerability
Erlang Erlang/OTP
Erlang/OTP is a set of libraries for the Erlang programming language. Prior to versions OTP-27.3.3, OTP-26.2.5.11, and OTP-25.3.2.20, a SSH server may allow an attacker to perform unauthenticated remote code execution (RCE). By exploiting a flaw in SSH protocol message handling, a malicious actor could gain unauthorized access to affected systems and execute arbitrary commands without valid credentials. This issue is patched in versions OTP-27.3.3, OTP-26.2.5.11, and OTP-25.3.2.20. A temporary workaround involves disabling the SSH server or to prevent access via firewall rules.
Ransomware groups exploiting CVE-2025-32433
The Gentlemen is a RaaS group that emerged in July–August 2025, rapidly claiming over 320 victims across 17+ countries by offering affiliates a 90% revenue share, deploying a Go-based locker against Windows, Linux, NAS, and BSD systems; a compromised C2 server
Exploitation is attributed to these groups across their recorded activity. It does not follow that every organisation they listed was reached through CVE-2025-32433 — the source data does not record an entry point per incident.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 9 June 2025. US federal agencies were required to remediate it by 30 June 2025.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 98.6%, which is higher than 99.9% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Recent listings by these groups
Disclosures from the groups above, newest first.
Frequently asked questions
Is CVE-2025-32433 being exploited by ransomware groups?
Yes. CVE-2025-32433 is recorded as exploited by Thegentlemen. Between them these groups account for 840 victim disclosures in this database.
What does CVE-2025-32433 affect?
CVE-2025-32433 affects Erlang Erlang/OTP. Erlang/OTP is a set of libraries for the Erlang programming language. Prior to versions OTP-27.3.3, OTP-26.2.5.11, and OTP-25.3.2.20, a SSH server may allow an attacker to perform unauthenticated remote code execution (RCE). By exploiting a flaw in SSH protocol message handling, a malicious actor could gain unauthorized access to affected systems and execute arbitrary commands without valid credentials. This issue is patched in versions OTP-27.3.3, OTP-26.2.5.11, and OTP-25.3.2.20. A temporary workaround involves disabling the SSH server or to prevent access via firewall rules.
How severe is CVE-2025-32433?
CVE-2025-32433 is rated CRITICAL with a CVSS base score of 10. EPSS puts the probability of exploitation in the next 30 days at 98.6%, higher than 99.9% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 30 June 2025.
How should organisations respond to CVE-2025-32433?
Apply the vendor patch for Erlang Erlang/OTP as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.