Is there a public exploit for CVE-2026-123204?

No public exploit for CVE-2026-123204 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-2026-123204?

CVE-2026-123204 scores CVSS 5.3 (v4.0), rated medium.

What does CVE-2026-123204 affect?

CVE-2026-123204 affects goposta posta.

5.3 Medium

Posta before v0.18.0 contains a server-side request forgery vulnerability that allows authenticated users with edit rights to make the…

CVE-2026-123204

Posta before v0.18.0 contains a server-side request forgery vulnerability that allows authenticated users with edit rights to make the backend send POST requests to internal destinations by creating webhooks with arbitrary URLs. Attackers can target loopback, private-network or cloud metadata addresses and read delivery status codes and error strings to probe internal hosts and ports.

Assessment

CVSS: 5.3 (v4.0)
Severity: Medium
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: goposta · posta
Assigner: VulnCheck

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

At the source

EUVD (ENISA)

References

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