dbcve.org
OS Command InjectionWeakness · CWE-78

CVE-2026-57999

HIGH · 8.8 CVSS v3.1 Published 2026-06-29
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click 7 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
luci-app-tailscale-community contains a command injection vulnerability in the tailscale.do_login RPC method that allows authenticated users to execute arbitrary commands as root. The vulnerability exists because user-controlled loginserver and loginserver_authkey parameters are improperly quoted within a double-quoted shell command, allowing shell substitutions like $() to be evaluated by the outer shell before argument processing.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Command injection vulnerability in the tailscale.do_login RPC method of luci-app-tailscale-community where the loginserver and loginserver_authkey parameters are embedded into a double-quoted shell command without proper sanitization. The double-quoting allows $() shell substitution, enabling authenticated attackers to execute arbitrary commands as root.

MitigationImplement strict input validation to strip or reject shell metacharacters ($(), |, &, ;, etc.) from the loginserver and loginserver_authkey parameters, and use safe argument passing methods instead of shell string interpolation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify luci-app-tailscale-community is installed
    On the OpenWrt/LEDE router, run 'opkg list-installed | grep luci-app-tailscale' or check via LuCI System > Software interface
    Affected if The package appears in the installed list
  2. Determine the installed version
    Run 'opkg info luci-app-tailscale-community | grep Version' to retrieve the exact version number
    Affected if Version cannot be determined or is earlier than any patched release
  3. Confirm tailscale RPC interface is enabled
    Check UCI configuration: look for 'config tailscale' section in /etc/config/tailscale or /etc/config/luci_tailscale, verify the 'rpc' or 'api' option is set to '1' or enabled
    Affected if The RPC interface is enabled and accessible remotely or via the web interface
  4. Verify the do_login RPC method is exposed
    Test for the existence of the tailscale.do_login method by examining the LuCI RPC router configuration or by querying the JSON-RPC endpoint at /cgi-bin/luci/rpc/tailscale with an empty auth payload to enumerate available methods
    Affected if The do_login method is listed as an available RPC method

A system is affected if luci-app-tailscale-community is installed with its RPC interface enabled, allowing external access to the vulnerable tailscale.do_login method with controllable loginserver or loginserver_authkey parameters.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict input validation to strip or reject shell metacharacters ($(), |, &, ;, etc.) from the loginserver and loginserver_authkey parameters, and use safe argument passing methods instead of shell string interpolation.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-57999 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-57999 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data