CVE catalog

CVE-2026-100888

Severity: High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: Sep 27, 2026, 11:30:16 PM UTC
Updated: Sep 28, 2026, 12:16:32 AM UTC
Source: [NVD] · [CVE record]
EPSS: 0.29% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	opendkim	sid	`2.11.0~beta2-9.2`	vulnerable
Debian	opendkim	forky	`2.11.0~beta2-9.2`	vulnerable
Debian	opendkim	trixie	`2.11.0~beta2-9.1`	vulnerable
Debian	opendkim	bookworm	`2.11.0~beta2-8+deb12u1`	vulnerable

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	opendkim	source	sid	`(unfixed)`	not yet assigned	Not reported	[1149875]
Debian	opendkim	source	forky	`(unfixed)`	not yet assigned	Not reported	[1149875]
Debian	opendkim	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1149875]
Debian	opendkim	source	bookworm	`(unfixed)`	not yet assigned	Not reported	[1149875]

[Debian bug #1149875]

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libopendkim11]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[libopendkim-dev]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[librbl1]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[librbl-dev]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[libvbr2]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[libvbr-dev]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[miltertest]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[opendkim]Affected
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
[opendkim-tools]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-8+deb12u1 · amd64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12
- 2.11.0~beta2-8+deb12u1 · arm64 · bookworm
  Affected
  nvd · opendkim · debian · bookworm; nvd · opendkim · debian · 12

[Debian 13 (Trixie)]

[libopendkim11]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[libopendkim-dev]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[librbl1]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[librbl-dev]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[libvbr2]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[libvbr-dev]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[miltertest]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[opendkim]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13
[opendkim-tools]Affected
Source package: [opendkim]
Details (2)
- 2.11.0~beta2-9.1+b1 · amd64 · trixie
  Affected
  nvd · opendkim · debian · 13
- 2.11.0~beta2-9.1+b1 · arm64 · trixie
  Affected
  nvd · opendkim · debian · 13

Observed: Oct 23, 2026, 7:48:11 PM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]