CVE-2026-127121 (GCVE-0-2026-127121)

Vulnerability from cvelistv5 – Published: 2026-11-12 15:55 – Updated: 2026-11-12 17:17 X_Open Source
VLAI
Title
SOGo before 5.12.13 S/MIME Certificate Spoofing via UIxMailView
Summary
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.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-12 16:38 UTC
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 8186 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Alinto sogo Affected: 0 , < 5.12.13 (semver)
guessed Create a notification for this product.
Date Public
2026-11-12 00:00
Credits
Richard Olszynský
Show details on NVD website
To clipboard 

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