Vault's PKI secrets engine ACME server did not restrict certificate identities that ACME challenges do not validate when issuing certificates under the default directory policy. This may allow an ACME client to obtain a certificate containing unverified identity claims, potentially enabling impersonation toward systems that trust certificates issued by the affected Vault PKI mount. This vulnerability (CVE-2026-105818) is fixed in Vault Community Edition 2.1.2, and Vault Enterprise 2.1.2, 1.21.12, 1.20.17, and 1.19.23.
PUBLISHED5.2CWE-345
Vault PKI ACME Issues Certificate With Unvalidated SANs
Problem type
Affected products
HashiCorp
Vault
< 2.1.2 - AFFECTED
Vault Enterprise
< 2.1.2 - AFFECTED
References
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-105818Click to expand
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"assignerShortName": "HashiCorp",
"dateUpdated": "2026-10-07T21:21:05.675Z",
"dateReserved": "2026-10-05T21:29:09.727Z",
"datePublished": "2026-10-07T21:21:05.675Z",
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"title": "Vault PKI ACME Issues Certificate With Unvalidated SANs",
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"references": [
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"url": "https://discuss.hashicorp.com/t/hcsec-2026-40-vault-pki-acme-default-directory-policy-may-issue-certificates-with-unverified-identities/77812"
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