CVE-2026-100891

A vulnerability has been found in Trusted Domain Project OpenDMARC up to 1.4.2. Affected by this issue is the function opendmarc_policy_query_dmarc in the library libopendmarc/opendmarc_policy.c of the component Internationalized Domain Name Handler. Such manipulation leads to encoding error. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

CVSS v3 7.3 HIGH
CVSS v2.0 7.5 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://vuldb.com/cve/CVE-2026-100891
https://vuldb.com/submit/917215
https://vuldb.com/vuln/410841
https://vuldb.com/vuln/410841/cti
https://weitongli.com/share/opendmarc-ulabel-not-converted.html

Configurations

No configuration.

History

28 Sep 2026, 01:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-28 01:16

Updated : 2026-10-01 14:17

NVD link : CVE-2026-100891

Mitre link : CVE-2026-100891

CVE.ORG link : CVE-2026-100891

JSON object : View

Products Affected

No product.

CWE

CWE-172

Encoding Error

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