CVE-2026-100888

A weakness has been identified in Trusted Domain Project OpenDKIM up to 2.11.0. This affects the function dkim_canon_selecthdrs of the file libopendkim/dkim-canon.c of the component DKIM Signature Header Selection. Executing a manipulation of the argument h can lead to out-of-bounds write. The attack can be executed remotely. The exploit has been made available to the public and could be used for attacks. 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-2026-100888
https://vuldb.com/submit/917015
https://vuldb.com/vuln/410837
https://vuldb.com/vuln/410837/cti
https://weitongli.com/share/opendkim-h-tag-oob-write.html

Configurations

No configuration.

History

28 Sep 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-28 00:16

Updated : 2026-09-30 23:16

NVD link : CVE-2026-100888

Mitre link : CVE-2026-100888

CVE.ORG link : CVE-2026-100888

JSON object : View

Products Affected

No product.

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE-787

Out-of-bounds Write

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