CVE-2023-47539 — An improper access control vulnerability in FortiMail version 7

An improper access control vulnerability in FortiMail version 7.4.0 configured with RADIUS authentication and remote_wildcard enabled may allow a remote unauthenticated attacker to bypass admin login via a crafted HTTP request.

01What is this vulnerability?

An improper access control vulnerability in FortiMail version 7.4.0 configured with RADIUS authentication and remote_wildcard enabled may allow a remote unauthenticated attacker to bypass admin login via a crafted HTTP request.

02Affected products

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2025-03-18T13:56:56.681Z
• Last modified: 2026-02-26T19:09:24.249Z

09References

• fortiguard.com — https://fortiguard.com/psirt/FG-IR-23-439