CVE-2026-127121
HIGH
MEDIUM
Priority: 0.01
BB Relevance:
64/100
Published: 2026-11-12
Modified: 2026-11-12
First seen: 2026-11-12
Status: active
Attack Surface
Network
Low Complexity
No Auth
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
Passive
S:
X
AT:
None
VC:
None
VI:
High
VA:
None
Description
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.
Weakness Classification (1)
References & Advisories (2)
third-party-advisory
patch
release-notes