---
id: CVE-2026-101280
title: A vulnerability was detected in Trusted Domain Project OpenDMARC up to 1.4.2
summary: >-
  A vulnerability was detected in Trusted Domain Project OpenDMARC up to 1.4.2.
  Affected is the function opendmarc_policy_query_dmarc of the component
  Multi-Record Set Handler. The manipulation results in authentication bypass by
  spoofing.…
severity: high
cvss: 7.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L'
cwe:
  - CWE-287
  - CWE-290
vendor: Trusted Domain Project
product: OpenDMARC
affected:
  - OpenDMARC 1.4.0
  - OpenDMARC 1.4.1
  - OpenDMARC 1.4.2
published: '2026-09-29'
updated: '2026-09-29'
sourceUpdated: '2026-09-29T18:57:24.350'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-101280'
references:
  - url: 'https://vuldb.com/cve/CVE-2026-101280'
    label: cna@vuldb.com
  - url: 'https://vuldb.com/submit/918282'
    label: cna@vuldb.com
  - url: 'https://vuldb.com/vuln/411037'
    label: cna@vuldb.com
  - url: 'https://vuldb.com/vuln/411037/cti'
    label: cna@vuldb.com
  - url: 'https://xuyongzhe-vt.github.io/share/opendmarc-multi-record-downgrade.html'
    label: cna@vuldb.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-101280.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-101280'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-101280'
tags:
  - nvd
  - cve.org
  - exploit-available
  - csaf
  - vex
  - red-hat
epss: 0.00403
epssPercentile: 0.34373
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-29T17:28:27.053437Z'
ingestedAt: '2026-09-29T01:24:51.144Z'
---

## Overview

A vulnerability was detected in Trusted Domain Project OpenDMARC up to 1.4.2. Affected is the function opendmarc_policy_query_dmarc of the component Multi-Record Set Handler. The manipulation results in authentication bypass by spoofing. The attack can be executed remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · updated 2026-09-29 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-101280.json)