High 8.2Published Oct 16, 2026

CVE-2026-86009Mailu: Domain managers can allow themselves to spoof on other hosted domains they should not control

Updated under an hour ago (2026-10-19 11:00 UTC)

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It affects Mailu. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Mailu

Exploited in the last 30 days

Mailu is a mail server distributed as a set of Docker images. Prior to f05aeb8322e2f61096af6b089d61ba6f40587d96, domain managers can enable spoofing for hosted domains they do not control. A potentially malicious domain administrator enables spoofing for another hosted domain and can send emails that are authenticated with DKIM/SPF for domains they should not be able to. This vulnerability is addressed by f05aeb8322e2f61096af6b089d61ba6f40587d96.

CVSS: 8.2 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N
Weakness (CWE): CWE-285, CWE-863
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Oct 16, 2026
First seen by InfoSec Signals: Oct 16, 2026

Affected products

Affected products

Mailu Mailu mailu:mailu (from the name)	before f05aeb8322e2f61096af6b089d61ba6f40587d96	CNA record

References

https://github.com/Mailu/Mailu/security/advisories/GHSA-crww-m82r-2wfmx-refsource-confirm
https://github.com/Mailu/Mailu/issues/2686x-refsource-misc
https://github.com/Mailu/Mailu/pull/4072x-refsource-misc
https://github.com/Mailu/Mailu/commit/f05aeb8322e2f61096af6b089d61ba6f40587d96x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.