Nixpkgs security tracker

Login with GitHub

Details of issue NIXPKGS-2026-2225

NIXPKGS-2026-2225
published 6 hours ago
AsyncSSH `AuthorizedKeysFile %u` path traversal allows attacker-selected authorized keys to authenticate a traversal username
Permalink CVE-2026-45309
8.2 HIGH
  • CVSS version (CVSS): 4.0
  • Attack Vector (AV): Network (N)
  • Attack Complexity (AC): Low (L)
  • Attack Requirement (AT): Present (P)
  • Privileges Required (PR): None (N)
  • User Interaction (UI): None (N)
  • Vulnerable System Impact Confidentiality (VC): None (N)
  • Vulnerable System Impact Integrity (VI): High (H)
  • Vulnerable System Impact Availability (VA): None (N)
  • Subsequent System Impact Confidentiality (SC): None (N)
  • Subsequent System Impact Integrity (SI): None (N)
  • Subsequent System Impact Availability (SA): None (N)
  • Modified Attack Vector (MAV): Network (N)
  • Modified Attack Complexity (MAC): Low (L)
  • Modified Attack Requirement (MAT): Present (P)
  • Modified Privileges Required (MPR): None (N)
  • Modified User Interaction (MUI): None (N)
  • Modified Vulnerable System Impact Confidentiality (MVC): None (N)
  • Modified Vulnerable System Impact Integrity (MVI): High (H)
  • Modified Vulnerable System Impact Availability (MVA): None (N)
  • Modified Subsequent System Impact Confidentiality (MSC): Negligible (N)
  • Modified Subsequent System Impact Integrity (MSI): Negligible (N)
  • Modified Subsequent System Impact Availability (MSA): Negligible (N)
  • Safety (S): Not Defined (X)
  • Automatable (AU): Not Defined (X)
  • Recovery (R): Not Defined (X)
  • Value Density (V): Not Defined (X)
  • Vulnerability Response Effort (RE): Not Defined (X)
  • Provider Urgency (U): Not Defined (X)
  • Confidentiality Req. (CR): Not Defined (X)
  • Integrity Req. (IR): Not Defined (X)
  • Availability Req. (AR): Not Defined (X)
  • Exploit Maturity (E): Not Defined (X)
updated 6 hours ago by @LeSuisse Activity log
  • Created suggestion 1 day, 3 hours ago
  • @LeSuisse accepted 7 hours ago
  • @LeSuisse published on GitHub 6 hours ago
AsyncSSH `AuthorizedKeysFile %u` path traversal allows attacker-selected authorized keys to authenticate a traversal username

AsyncSSH is a Python package which provides an asynchronous client and server implementation of the SSHv2 protocol on top of the Python asyncio framework. Prior to 2.23.0, AsyncSSH expands the OpenSSH-compatible AuthorizedKeysFile %u token in asyncssh/config.py, asyncssh/connection.py, asyncssh/auth_keys.py, and asyncssh/misc.py with the raw SSH username during pre-authentication server config reload, allowing a server configured with AuthorizedKeysFile authorized_keys/%u to read an authorized-keys file outside the intended directory when the SSH username contains /, \, or .. path traversal segments and authenticate with an attacker-selected key file. This issue is fixed in version 2.23.0.

Affected products

asyncssh
  • ==< 2.23.0

Matching in nixpkgs