CVE-2023-28436

Elevated group privileges via skipped setgid call

Published Mar 23, 2023 · Updated Feb 25, 2025

Improper privilege management in Tailscale SSH 1.34.0 through 1.38.1 allows remote authenticated users to run commands with a higher group ID. The non-interactive SSH incubator calls setgroups before checking the effective GID; on FreeBSD, setgroups changes that GID, so the later comparison skips setgid and the child inherits tailscaled's group. Exploitation requires Tailscale SSH enabled, rules allowing a non-root account, and a non-interactive session; the bounded consequence is command execution with unintended group access.

CVSS severity5.7
Medium
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper privilege management in Tailscale SSH 1.34.0 through 1.38.1 allows remote authenticated users to run commands with a higher group ID. The non-interactive SSH incubator calls setgroups before checking the effective GID; on FreeBSD, setgroups changes that GID, so the later comparison skips setgid and the child inherits tailscaled's group. Exploitation requires Tailscale SSH enabled, rules allowing a non-root account, and a non-interactive session; the bounded consequence is command execution with unintended group access.

The record

CVE
CVE-2023-28436
Published
Mar 23, 2023
Updated
Feb 25, 2025
Vendor
Tailscale
Product
Tailscale
Classifications
CWE-277, T1068
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 25, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 1.34.0, < 1.38.2

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

Tailscale · Tailscaleversion=>= 1.34.0, < 1.38.2

Published CVSS scores

5.7TailscaleCVSS:3.0/AV:A/AC:L/PR:H/UI:R/S:C/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-277Insecure Inherited Permissions
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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