CVE-2026-71543: OpenBao's Templated Policies Allow Privilege Escalation via Wildcard Characters
OpenBao is an open source identity-based secrets management system. Prior to 2.6.0, templated ACL, PKI, and SSH policies could substitute attacker-controlled identity data without rejecting syntax-significant characters. In ACL templated policies, asterisks, plus signs, and slashes could alter path matching. In PKI allowedurisanstemplate and alloweddomains policies, an asterisk could broaden certificate issuance to unauthorized domains. In SSH allowedusers and alloweddomains policies, a comma could add unauthorized principals. Exploitation requires a deployment to use templated policy data that users can freely modify; templates based on the randomly generated identity.entity.id value are not affected. This could allow privilege escalation, unauthorized access, and unauthorized certificate issuance. This issue is fixed in version 2.6.0.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
OpenBaoto a version that resolves this vulnerability.Fixed in 2.6.0
Event History
Frequently Asked Questions
Which deployments are actually exposed to this issue?
Exposure requires templated ACL, PKI, or SSH policy fields that substitute identity data users can freely modify. Templates using the randomly generated identity.entity.id value are not affected.
What attacker-controlled characters are relevant for each policy type?
For ACL templated policies, asterisks, plus signs, and slashes can change path matching. For PKI allowed_uri_sans_template and allowed_domains policies, an asterisk can broaden certificate issuance; for SSH allowed_users and allowed_domains policies, a comma can add unauthorized principals.
What is the remediation?
Upgrade OpenBao to version 2.6.0, which fixes the issue. Until upgrading, review templated policy data and avoid using user-modifiable identity values in the affected ACL, PKI, and SSH policy fields.