CVE-2023-28436Non-interactive Tailscale SSH sessions on FreeBSD may use the effective group ID of the tailscaled process
- 5.7MediumCVSS base score
- 0.46%Exploitation in 30 daysEPSS · top 59% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By GitHub_M
- 8 days later
· 8 days later
Published
- 24 months later
· 24 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.7 | CVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:C/C:H/I:N/A:N |
| NVDNVD · Modified | 3.1 | High8.0 | CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.46% · top 59% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.7.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gotailscale.comGHSA-vfgq-g5x8-g595 (opens in a new tab)
References
References4
- https://github.com/tailscale/tailscale/security/advisories/GHSA-vfgq-g5x8-g595 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/tailscale/tailscale/commit/d00c046b723dff6e3775d7d35f891403ac21a47d (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/tailscale/tailscale/releases/tag/v1.38.2 (opens in a new tab)x_refsource_MISCx_transferred
- https://tailscale.com/security-bulletins/#ts-2023-003 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2023-1110 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-vfgq-g5x8-g595 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2023-28436)Record last updated .