---
id: CVE-2025-61984
title: >-
  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
summary: >-
  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 %…
severity: low
cvss: 3.6
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N'
cwe:
  - CWE-159
vendor: OpenBSD
product: OpenSSH
affected:
  - OpenSSH < 10.1
published: '2025-10-06'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T02:18:09.487'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-61984'
references:
  - url: 'https://marc.info/?l=openssh-unix-dev&m=175974522032149&w=2'
    label: cve@mitre.org
  - url: 'https://www.openssh.com/releasenotes.html#10.1p1'
    label: cve@mitre.org
  - url: 'https://www.openwall.com/lists/oss-security/2025/10/06/1'
    label: cve@mitre.org
  - url: 'http://www.openwall.com/lists/oss-security/2025/10/07/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2025/10/12/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.vicarius.io/vsociety/posts/cve-2025-61984-detection-script-remote-code-execution-vulnerability-affecting-openssh
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.vicarius.io/vsociety/posts/cve-2025-61984-mitigation-script-remote-code-execution-vulnerability-affecting-openssh
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-019113.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-457936.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://dgl.cx/2025/10/bash-a-newline-ssh-proxycommand-cve-2025-61984'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - exploit-available
  - cve.org
epss: 0.00463
epssPercentile: 0.39958
exploits:
  github: 2
  githubRepos:
    - 'https://github.com/dgl/cve-2025-61984-poc'
    - 'https://github.com/flyskyfire/cve-2025-61984-poc'
  checkedAt: '2026-10-27T16:48:18.560Z'
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2025-10-08T03:55:10.734755Z'
ingestedAt: '2026-09-08T15:33:26.996Z'
---

## Overview

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.)

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.