CVE-2023-28436

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Source
https://nvd.nist.gov/vuln/detail/CVE-2023-28436
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2023-28436.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2023-28436
Aliases
Published
2023-03-23T19:27:48.051Z
Modified
2025-11-29T14:10:27.184386Z
Severity
  • 5.7 (Medium) CVSS_V3 - CVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:C/C:H/I:N/A:N CVSS Calculator
Summary
Non-interactive Tailscale SSH sessions on FreeBSD may use the effective group ID of the tailscaled process
Details

Tailscale is software for using Wireguard and multi-factor authentication (MFA). A vulnerability identified in the implementation of Tailscale SSH starting in version 1.34.0 and prior to prior to 1.38.2 in FreeBSD allows commands to be run with a higher privilege group ID than that specified in Tailscale SSH access rules. A difference in the behavior of the FreeBSD setgroups system call from POSIX meant that the Tailscale client running on a FreeBSD-based operating system did not appropriately restrict groups on the host when using Tailscale SSH. When accessing a FreeBSD host over Tailscale SSH, the egid of the tailscaled process was used instead of that of the user specified in Tailscale SSH access rules.

Tailscale SSH commands may have been run with a higher privilege group ID than that specified in Tailscale SSH access rules if they met all of the following criteria: the destination node was a FreeBSD device with Tailscale SSH enabled; Tailscale SSH access rules permitted access for non-root users; and a non-interactive SSH session was used.

Affected users should upgrade to version 1.38.2 to remediate the issue.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/28xxx/CVE-2023-28436.json",
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-269"
    ]
}
References

Affected packages

Git / github.com/tailscale/tailscale

Affected ranges

Type
GIT
Repo
https://github.com/tailscale/tailscale
Events
Introduced
988801d5d97287a276fc74cddb09a0e0ddf8afb7
Fixed
3db61d07ca81aea7b86591d1874e48db01b6abcf