Is there a public exploit for CVE-2026-127121?

No public exploit for CVE-2026-127121 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-2026-127121?

CVE-2026-127121 scores CVSS 7.1 (v4.0), rated high.

What does CVE-2026-127121 affect?

CVE-2026-127121 affects Alinto SOGo.

7.1 High

SOGo before 5.12.13 contains an improper cryptographic signature verification vulnerability that allows remote attackers to replace a…

CVE-2026-127121

SOGo before 5.12.13 contains an improper cryptographic signature verification vulnerability that allows remote attackers to replace a victim's contact S/MIME certificate by sending a spoofed multipart/signed message with a mismatched signature and an impersonated From address. Attackers can deliver a crafted CMS signedData object containing their own self-signed certificate, which SOGo's UIxMailView stores on the contact card without validating signature authenticity or certificate identity, enabling subsequent encrypted communications to be decrypted with the attacker's private key.

Assessment

CVSS: 7.1 (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: 12 November 2026
Last updated: 12 November 2026
Affected: Alinto · SOGo
Assigner: VulnCheck

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

At the source

EUVD (ENISA)

References

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