UBUNTU-CVE-2026-45309

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Source
https://ubuntu.com/security/CVE-2026-45309
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-45309
Upstream
Published
2026-07-17T19:17:00Z
Modified
2026-08-04T11:00:09Z
Severity
  • 8.2 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N CVSS Calculator
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

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.

References

Affected packages

Ubuntu:16.04:LTS
python-asyncssh

Package

Name
python-asyncssh
Purl
pkg:deb/ubuntu/python-asyncssh?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.2.0-1
1.2.1-1
1.3.0-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python3-asyncssh",
            "binary_version": "1.3.0-1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json"
Ubuntu:20.04:LTS
python-asyncssh

Package

Name
python-asyncssh
Purl
pkg:deb/ubuntu/python-asyncssh?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.12.2-1
1.12.2-1ubuntu0.1
1.12.2-1ubuntu0.2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python3-asyncssh",
            "binary_version": "1.12.2-1ubuntu0.2"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json"
Ubuntu:26.04:LTS
python-asyncssh

Package

Name
python-asyncssh
Purl
pkg:deb/ubuntu/python-asyncssh?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.20.0-1
2.21.1-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python3-asyncssh",
            "binary_version": "2.21.1-1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json"
Ubuntu:Pro:18.04:LTS
python-asyncssh

Package

Name
python-asyncssh
Purl
pkg:deb/ubuntu/python-asyncssh?arch=source&distro=esm-apps%2Fbionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.8.1-2
1.11.0-2
1.11.1-1
1.11.1-1ubuntu0.1~esm1
1.11.1-1ubuntu0.1~esm2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python3-asyncssh",
            "binary_version": "1.11.1-1ubuntu0.1~esm2"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json"
Ubuntu:Pro:22.04:LTS
python-asyncssh

Package

Name
python-asyncssh
Purl
pkg:deb/ubuntu/python-asyncssh?arch=source&distro=esm-apps%2Fjammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.5.0-1
2.5.0-1ubuntu0.1~esm1
2.5.0-1ubuntu0.1
2.5.0-1ubuntu0.1+esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python3-asyncssh",
            "binary_version": "2.5.0-1ubuntu0.1+esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json"
Ubuntu:Pro:24.04:LTS
python-asyncssh

Package

Name
python-asyncssh
Purl
pkg:deb/ubuntu/python-asyncssh?arch=source&distro=esm-apps%2Fnoble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.10.1-2
2.10.1-2ubuntu0.1
2.10.1-2ubuntu0.1+esm1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "python3-asyncssh",
            "binary_version": "2.10.1-2ubuntu0.1+esm1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-45309.json"