CVE-2026-100889 (GCVE-0-2026-100889)

Vulnerability from cvelistv5 – Published: 2026-09-27 23:45 – Updated: 2026-09-27 23:45
VLAI
Title
Trusted Domain Project OpenDKIM Decoder util.c dkim_qp_decode off-by-one
Summary
A vulnerability was detected in Trusted Domain Project OpenDKIM up to 2.11.0. Affected is the function dkim_qp_decode of the file util.c of the component Decoder. The manipulation results in off-by-one. The attack may be performed from remote. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:C
7.3 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:C
CWE
Assigner
References
URL Tags
https://vuldb.com/vuln/410839 vdb-entrytechnical-description
https://vuldb.com/vuln/410839/cti signaturepermissions-required
https://vuldb.com/cve/CVE-2026-100889 third-party-advisory
https://vuldb.com/submit/917063 third-party-advisory
https://weitongli.com/share/opendkim-qp-off-by-one.html exploit
Impacted products
Vendor Product Version CPE status
Trusted Domain Project OpenDKIM Affected: 2.0
Affected: 2.1
Affected: 2.2
Affected: 2.3
Affected: 2.4
Affected: 2.5
Affected: 2.6
Affected: 2.7
Affected: 2.8
Affected: 2.9
Affected: 2.10
Affected: 2.11.0
    cpe:2.3:a:trusted_domain_project:opendkim:*:*:*:*:*:*:*:*
Create a notification for this product.
Credits
WeitongLi (VulDB User) VulDB CNA Team
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "cpes": [
            "cpe:2.3:a:trusted_domain_project:opendkim:*:*:*:*:*:*:*:*"
          ],
          "modules": [
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          "product": "OpenDKIM",
          "vendor": "Trusted Domain Project",
          "versions": [
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              "version": "2.0"
            },
            {
              "status": "affected",
              "version": "2.1"
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            {
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            },
            {
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              "version": "2.4"
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          "type": "reporter",
          "value": "WeitongLi (VulDB User)"
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        }
      ],
      "metrics": [
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          "time": "2026-09-27T09:41:07.000Z",
          "value": "VulDB entry last update"
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  },
  "cveMetadata": {
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    "assignerShortName": "VulDB",
    "cveId": "CVE-2026-100889",
    "datePublished": "2026-09-27T23:45:16.286Z",
    "dateReserved": "2026-09-27T07:35:55.983Z",
    "dateUpdated": "2026-09-27T23:45:16.286Z",
    "state": "PUBLISHED"
  },
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  "dataVersion": "5.2",
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                "vendor": "Trusted Domain Project",
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          }
        ],
        "id": "CVE-2026-100889",
        "lastModified": "2026-09-28T00:16:32.647",
        "metrics": {
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                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
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            "url": "https://weitongli.com/share/opendkim-qp-off-by-one.html"
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      "cve": "CVE-2026-100889",
      "id": "CVE-2026-100889",
      "initial_release_date": "2026-09-27T23:45:16.286000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "opendkim: opendkim: Denial of Service via off-by-one error in dkim_qp_decode",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100889.json",
      "version": "3"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.