Is there a public exploit for CVE-2026-121139?

No public exploit for CVE-2026-121139 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121139?

CVE-2026-121139 scores CVSS 7.3 (v4.0), rated high.

What does CVE-2026-121139 affect?

CVE-2026-121139 affects Rapid7 Metasploit Framework.

7.3 High

The Rapid7 Metasploit msf-ws suffers from a missing authentication vulnerability whereby the REST API grants an unauthenticated "bootstrap"…

CVE-2026-121139

The Rapid7 Metasploit msf-ws suffers from a missing authentication vulnerability whereby the REST API grants an unauthenticated "bootstrap" exemption so that the very first administrator can be created when the users table is empty. While the table is empty, POST /api/v1/users is exempt from authentication by design: the route handler calls warden.authenticate!(scope: :adminapi), which resolves to AdminApiToken. The inherited ApiToken#authenticate! short-circuits and returns success!() whenever msf.authinitialized is false, without ever evaluating AdminApiToken's administrator check. In that state the endpoint creates a user — including an administrator — for an entirely unauthenticated caller. This issue has been fixed in version 6.5.9.

Assessment

CVSS: 7.3 (v4.0)
Severity: High
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 5 November 2026
Last updated: 5 November 2026
Affected: Rapid7 · Metasploit Framework
Assigner: rapid7

CVSS vectorCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

https://github.com/rapid7/metasploit-framework/pull/22039

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