Auth bypass in Trusted Domain Project Opendmarc
CVE-2026-101281
A flaw has been found in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this vulnerability is the function opendmarc_sp2_find_mailfrom_domain of the file libopendmarc/opendmarc_spf.c of the component SPF Macro Handler. This manipulation causes improper authentication. The attack is possible to be carried out remotely. The exploit has been published and may be used. Patch name: c48a74c758677fc5272a73eff15ffdbf8afda1a6. Applying a patch is the recommended action to fix this issue.
Vulnerability class: Broken Authentication
Published .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Trusted Domain Project Opendmarc — versions 1.4.0, 1.4.1, 1.4.2
Weakness classification (CWE)
References
- vuldb.com/vuln/411038 (technical-description, vdb-entry)
- vuldb.com/vuln/411038/cti (signature, permissions-required)
- vuldb.com/cve/CVE-2026-101281 (third-party-advisory)
- vuldb.com/submit/918284 (third-party-advisory)
- github.com/trusteddomainproject/OpenDMARC/issues/262 (issue-tracking)
- github.com/trusteddomainproject/OpenDMARC/pull/328 (issue-tracking, patch)
- xuyongzhe-vt.github.io/share/opendmarc-spf-postmaster-macro.html (exploit)
- github.com/trusteddomainproject/OpenDMARC/commit/c48a74c758677fc5272a73eff15ffd… (patch)
Frequently asked questions
- What is CVE-2026-101281?
- CVE-2026-101281 is a high-severity vulnerability in Trusted Domain Project Opendmarc, classified under Improper Authentication. CVSS score: 7.3/10. Published 2026-09-29.
- How severe is CVE-2026-101281?
- High severity. CVSS v3 base score is 7.3 out of 10.