Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-100888
Trusted Domain Project OpenDKIM DKIM Signature Header Selection dkim-canon.c dkim_canon_selecthdrs out-of-bounds write
AV AC AT PR UI VC VI VA CVSS EPSS %ile KEV
N L N N N L L L 5.5 .0029 19.9 —
AFFECTED
Product Versions Fixed
OpenDKIM 2.0 – —
TIMELINE
Sep 27 Reserved by VulDB
Sep 27 Published (CNA: VulDB)
Sep 28 RESCORED — CVE-2026-100888 (Trusted Domain Project OpenDKIM). CVSS 6.9 → 5.5 (NVD).
Sep 30 EXPLOIT PUBLISHED — CVE-2026-100888 (Trusted Domain Project OpenDKIM). Public exploit reference added.
Description
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.
Lifecycle
Complete event history — 4 events, chronological
| Date | Event | Detail |
|---|
| September 27, 2026 | Reserved | Reserved by VulDB |
| September 27, 2026 | Published | Published (CNA: VulDB) |
| September 28, 2026 | RESCORED | RESCORED — CVE-2026-100888 (Trusted Domain Project OpenDKIM). CVSS 6.9 → 5.5 (NVD). |
| September 30, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-100888 (Trusted Domain Project OpenDKIM). Public exploit reference added. |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| Trusted Domain Project | OpenDKIM | — | 2.0 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-100888 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
