Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🛡️
Not in CISA KEV
HIGH severity

CVE-2026-101281 — Trusteddomainproject

HIGHFix: trusteddomainproject/OpenDMARC@c48a74c

CVE-2026-101281 is a high-severity (CVSS 7.3) Improper Authentication vulnerability. No vendor fix is recorded yet; mitigation options are listed below.

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…

Published
Sep 29, 2026
Updated
Sep 29, 2026
Affected
—
Patched
See advisory
Exploits
None indexed
Exploitation data as of Sep 29, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Description

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.

Detection & mitigation playbook

Vulnerability
  1. Detect

    Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

  2. Remediation status

    No fixed release is recorded for CVE-2026-101281 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.

  3. Mitigate without a patch

    Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Frequently Asked Questions

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.
O3 Security · Impact-Aware SCA

Is CVE-2026-101281 in your dependencies?

Find it across , including transitive dependencies.

CVE-2026-101281: Auth Bypass (High 7.3) | O3 Security