Medium severity · published Oct 7, 2026
CVE-2026-105820
Vault ACL Policy Cache Vulnerable to Cross-Namespace Policy Resolution
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
Vault's ACL policy cache allowed namespace traversal when policy names contained path traversal constructs. This may allow a token assigned specially crafted policy names to use the capabilities of policies defined in other namespaces, including the root namespace. This vulnerability (CVE-2026-105820) is fixed in Vault Enterprise 2.1.2, 1.21.12, 1.20.17, and 1.19.23. Vault Community Edition does not support namespaces, and is not affected.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
VE
Vault Enterprise · HashiCorp
0.0.1 before 2.1.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105820
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105820
discuss.hashicorp.com
https://discuss.hashicorp.com/t/hcsec-2026-42-vault-enterprise-acl-policy-cache-vulnerable-to-cross-namespace-policy-resolution/77814
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