Is CVE-2026-101016 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-101016 being exploited in the wild.

How severe is CVE-2026-101016?

Medium severity, with a CVSS score of 6.5, published 28 September 2026.

Which products and versions are affected?

Trusted Domain Project OpenDMARC up to 1.4.2.

Is there a fix for CVE-2026-101016?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-101016 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-101016?

Check whether you run Trusted Domain Project OpenDMARC at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-101016: Trusted Domain Project OpenDMARC exception handling in DMARC policy parsing

CVE-2026-101016 · Severity: medium · CVSS 6.5 · Published 2026-09-28

OpenDMARC is a library that validates email authenticity through DMARC policy checking. A vulnerability in policy parsing allows remote attackers to trigger unhandled exceptions by manipulating policy parameters, potentially disrupting email validation services. The vulnerability affects OpenDMARC versions up to 1.4.2 and has been publicly disclosed.

Technologies: Trusted Domain Project OpenDMARC. Vendors: Trusted Domain Project.

Quick answers

Is CVE-2026-101016 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-101016 being exploited in the wild.
How severe is CVE-2026-101016?: Medium severity, with a CVSS score of 6.5, published 28 September 2026.
Which products and versions are affected?: Trusted Domain Project OpenDMARC up to 1.4.2.
Is there a fix for CVE-2026-101016?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-101016 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-101016?: Check whether you run Trusted Domain Project OpenDMARC at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability exists in the opendmarc_policy_parse_dmarc function within libopendmarc/opendmarc_policy.c, where manipulation of DMARC policy arguments (fo, rf, ri, pct, sp, adkim, aspf, rua, ruf) leads to improper exception handling. Remote exploitation is possible without authentication, allowing an attacker to send malformed DMARC policies to trigger denial-of-service conditions in systems using this library.

Affected products

Trusted Domain Project OpenDMARC up to 1.4.2

Timeline

2026-09-28: disclosed

References

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