CVE-2026-55770
OpenBao is an open source identity-based secrets management system. Prior to 2.5.5, OpenBao used EscapeLDAPValue, an RFC 4514 distinguished-name escaping function, where RFC 4515 LDAP search-filter escaping was required in sdk/helper/ldaputil/client.go GetUserDN. With the LDAP authentication backend configured for an Active Directory UPNDomain path or UserDN and UserAttr binding, an attacker-controlled username containing filter metacharacters could alter the search predicate and select a different directory entry because EscapeLDAPValue does not neutralize the characters handled by ldap.EscapeFilter. A resulting token could be associated with another LDAP identity and gain access to secrets, policies, or modification capabilities assigned to that identity. This issue is fixed in version 2.5.5.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 38% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 6.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N- Weakness
- CWE-90
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-15
- Last modified
- 2026-09-17
- Sources
- NVD
References
- https://github.com/openbao/openbao/commit/10b7825c714c1ef25b6c3c1c2cd6ecd8747c0659
- https://github.com/openbao/openbao/commit/8077f96bdc02137b0a072146b6f9ca11c96c549c
- https://github.com/openbao/openbao/pull/3306
- https://github.com/openbao/openbao/pull/3313
- https://github.com/openbao/openbao/releases/tag/v2.5.5
- https://github.com/openbao/openbao/releases/tag/v2.6.0
- https://github.com/openbao/openbao/security/advisories/GHSA-6mwx-4547-5vc9
- https://github.com/openbao/openbao/security/advisories/GHSA-6mwx-4547-5vc9