Medium severity · published Oct 7, 2026
CVE-2026-105818
Vault PKI ACME Issues Certificate With Unvalidated SANs
5.9
CVSS
0.1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 0% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VA
Vault · HashiCorp
1.14.0 before 2.1.2 · source: vendor
VE
Vault Enterprise · HashiCorp
1.14.0 before 2.1.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105818
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105818
discuss.hashicorp.com
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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