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. 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.)
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
3.6 LOW
LOCAL
HIGH
LOW
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
mitreCNA
3.6 LOW
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
CISA-ADPADP
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CVEADP
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Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Debian logo
Debian Releases
Debian Product
Codename
openssh
bullseye
postponed
trixie
no-dsa
bookworm
no-dsa
bullseye (security)
vulnerable
bookworm (security)
vulnerable
forky
1:10.2p1-2
fixed
sid
1:10.2p1-2
fixed
Common Weakness Enumeration
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://dgl.cx/2025/10/bash-a-newline-ssh-proxycommand-cve-2025-61984