CVE-2026-29143 impacts SEPPmail Secure Email Gateway versions prior to 15.0.3, where improper authentication of inner messages in S/MIME-encrypted MIME entities allows an attacker to control trusted headers. This vulnerability carries a CVSSv4 score of 7.8 (High), indicating a remotely exploitable issue with low attack complexity that can lead to high integrity impacts, such as impersonation. There is currently no evidence of active exploitation, public exploit code, or significant community discussion, with its EPSS score suggesting a very low probability of exploitation.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 15.0.3CPE matchmatch criteria | cpe:2.3:a:seppmail:secure_email_gateway:*:*:*:*:*:*:*:* |
CVSS version used by this source: 4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.