What is CVE-2026-84697?

CVE-2026-84697 is a medium-severity vulnerability in Axllent Mailpit, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.3/10. Published 2026-09-02.

How severe is CVE-2026-84697?

Medium severity. CVSS v3 base score is 5.3 out of 10.

SSRF in Axllent Mailpit

CVE-2026-84697

Mailpit's IsInternalIP deny list function fails to block the Azure WireServer address 168.63.129.16 and the RFC 2765/6145 IPv4-translated IPv6 prefix, allowing server-side request forgery to internal destinations. Attackers can supply hostnames resolving to these addresses in message content to reach the link check API and proxy endpoint for accessing internal resources.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published 2026-09-02 · last modified 2026-09-10.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (32.4th percentile), scored 2026-10-17.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.002

Affected products

Axllent Mailpit

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

References

github.com/axllent/mailpit (product)
github.com/axllent/mailpit/blob/v1.31.0/internal/tools/net.go (technical-description)
github.com/axllent/mailpit/commit/a02821bf3424da9196e156c422370f4868a1dff2 (patch)
www.vulncheck.com/advisories/mailpit-ssrf-deny-list-bypass-via-azure-metadata-a… (third-party-advisory)

Frequently asked questions

What is CVE-2026-84697?: CVE-2026-84697 is a medium-severity vulnerability in Axllent Mailpit, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.3/10. Published 2026-09-02.
How severe is CVE-2026-84697?: Medium severity. CVSS v3 base score is 5.3 out of 10.