CVE-2025-61984
ssh in OpenSSH before 10.1 allows control characters in usernames that originate from certain possibly untrusted sources, potentially leading to code execution when a ProxyCommand is used.
Does this matter?
Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.
Description
ssh in OpenSSH before 10.1 allows control characters in usernames that originate from certain possibly untrusted sources, potentially leading to code execution when a ProxyCommand is used. The untrusted sources are the command line and %-sequence expansion of a configuration file. (A configuration file that provides a complete literal username is not categorized as an untrusted source.)
- CVSS 3.1
- 3.6 LOWCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
- EPSS
- 0.29% probability · 21th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-159
- Source
- cve@mitre.org
References
- https://marc.info/?l=openssh-unix-dev&m=175974522032149&w=2
- https://www.openssh.com/releasenotes.html#10.1p1
- https://www.openwall.com/lists/oss-security/2025/10/06/1
- http://www.openwall.com/lists/oss-security/2025/10/07/1
- http://www.openwall.com/lists/oss-security/2025/10/12/1
- https://www.vicarius.io/vsociety/posts/cve-2025-61984-detection-script-remote-code-execution-vulnerability-affecting-openssh
- https://www.vicarius.io/vsociety/posts/cve-2025-61984-mitigation-script-remote-code-execution-vulnerability-affecting-openssh
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://dgl.cx/2025/10/bash-a-newline-ssh-proxycommand-cve-2025-61984
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.