{"cve":"CVE-2023-28436","nvd":{"published":"2023-03-23T20:15:15.487","modified":"2026-06-17T05:47:44.060","status":"Modified","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.\n\nTailscale 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.\n\nAffected users should upgrade to version 1.38.2 to remediate the issue.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":8.0},"cwes":["CWE-269"],"references":["https://github.com/tailscale/tailscale/commit/d00c046b723dff6e3775d7d35f891403ac21a47d","https://github.com/tailscale/tailscale/releases/tag/v1.38.2","https://github.com/tailscale/tailscale/security/advisories/GHSA-vfgq-g5x8-g595","https://tailscale.com/security-bulletins/#ts-2023-003","https://github.com/tailscale/tailscale/commit/d00c046b723dff6e3775d7d35f891403ac21a47d"],"products":["tailscale:tailscale"],"source":"nvd","synced_at":"2026-10-19T21:37:48.383111019+00:00"},"epss":{"cve":"CVE-2023-28436","score":0.00464,"percentile":0.40206,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-vfgq-g5x8-g595","url":"https://osv.dev/vulnerability/GHSA-vfgq-g5x8-g595","summary":"Non-interactive Tailscale SSH sessions on FreeBSD may use the effective group ID of the tailscaled process","modified":"2026-09-10T03:49:56.848408585Z","packages":[{"ecosystem":"Go","name":"tailscale.com","purl":"pkg:golang/tailscale.com","ranges":[">=1.34.0 <1.38.2"],"fixed":["1.38.2"]}]},{"id":"GO-2023-1671","url":"https://osv.dev/vulnerability/GO-2023-1671","summary":"Non-interactive Tailscale SSH sessions on FreeBSD may use the effective group ID of the tailscaled process in tailscale.com","modified":"2026-03-03T04:53:33.742239Z","packages":[{"ecosystem":"Go","name":"tailscale.com","purl":"pkg:golang/tailscale.com","ranges":[">=1.34.0 <1.38.2"],"fixed":["1.38.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}