High
opendkim — security advisory
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.
- Products
- opendkim
- Affected versions
- 2.10.3-3build1, 2.11.0~alpha-10, 2.11.0~alpha-11, 2.11.0~alpha-11build1, 2.11.0~alpha-12, 2.11.0~alpha-13, 2.11.0~alpha-14, 2.11.0~beta2-1, 2.11.0~beta2-4build1, 2.11.0~beta2-5, 2.11.0~beta2-6, 2.11.0~beta2-8, 2.11.0~beta2-9, 2.11.0~beta2-9.2, 2.11.0~beta2-9.2build1, 2.11.0~beta2-9.2build2, 2.11.0~beta2-9build3, 2.11.0~beta2-9build4
- Fixed versions
- Not specified
- CVEs
- CVE-2026-100889
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:53 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-100889
opendkim
Fixed versions: Not specified
opendkim
Fixed versions: Not specified
opendkim
Fixed versions: Not specified
opendkim
Fixed versions: Not specified
opendkim
Fixed versions: Not specified
opendkim
Fixed versions: Not specified
opendkim
Fixed versions: Not specified
Complete source record
{
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"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-100889",
"method": "structured",
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"title": "UBUNTU-CVE-2026-100889",
"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.",
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],
"modified": "2026-10-17T12:59:43.175274155Z",
"provider": "osv",
"upstream": [
"CVE-2026-100889"
],
"references": [
"https://ubuntu.com/security/CVE-2026-100889",
"https://www.cve.org/CVERecord?id=CVE-2026-100889",
"https://weitongli.com/share/opendkim-qp-off-by-one.html",
"https://vuldb.com/cve/CVE-2026-100889",
"https://vuldb.com/submit/917063",
"https://vuldb.com/vuln/410839",
"https://vuldb.com/vuln/410839/cti"
]
},
"related_cves": [
{
"value": "CVE-2026-100889",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 359729,
"published_at": "2026-09-28T00:16:00+00:00"
}