SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-105818

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.

MEDIUM 5.9EPSS 0.08%

Does this matter?

Lower severity and a low EPSS score (0.08%). Track it; it rarely justifies an emergency change on its own.

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 3.1
5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
0.08% probability · 0th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-345
Source
security@hashicorp.com
EPSS trend
0%3%5%8 October 2026: 0.08%26 October 2026: 0.08%8 October 202626 October 2026

EPSS moved from 0.1% on 8 October 2026 to 0.1% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.