CVE-2026-105818
Vault PKI ACME Issues Certificate With Unvalidated SANs
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Vault PKI ACME Issues Certificate With Unvalidated SANs
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.
- Record
CVE-2026-105818- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-345
- Updated
- 2026-11-02
EUVDEUVD-2026-94641
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.
- Record
EUVD-2026-94641- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-fxww-hx7x-vxpc
Vault's PKI secrets engine ACME server did not restrict certificate identities that ACME...
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.
- Record
GHSA-fxww-hx7x-vxpc- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-345
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-105818- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-345
- Updated
- 2026-11-02
OSV
Vault PKI ACME Issues Certificate With Unvalidated SANs
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.
- Record
CVE-2026-105818- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-345
- Updated
- 2026-11-02
OSVBIT-vault-2026-105818 No score
Vault PKI ACME Issues Certificate With Unvalidated SANs
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.
- Record
BIT-vault-2026-105818- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
vaultBitnami |
1.14.0 up to 2.1.2 | 2.1.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-105818 is a medium vulnerability (CVSS 5.9) in Hashicorp Vault, published October 7, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.08%, the 0th percentile. Fixed in vault 2.1.2.
References
discuss.hashicorp.com/t/hcsec-2026-40-vault-pki-acme-default-directory-policy-may-issue-certificates-with-unverified-identities/77812
nvd.nist.gov/vuln/detail/CVE-2026-105818
github.com/advisories/GHSA-fxww-hx7x-vxpc