Open Access Management (OpenAM) is an access management solution. Prior to 16.1.1, WebAuthnAuthentication loads a serialized AuthenticatorImpl object graph from the configured userAttribute through loadAuthenticators without an ObjectInputFilter. Exploitation requires the WebAuthn flow to be reachable and an attacker to have previously written controlled data to that attribute through delegated administration, provisioning, directory access, legacy REST self-registration, or unsafe configuration. When those non-default conditions hold, the data is deserialized before assertion verification and can execute a classpath gadget in the application server process. This issue is fixed in version 16.1.1.
https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-6c99-87fr-6q7r
https://github.com/OpenIdentityPlatform/OpenAM/releases/tag/16.1.1
https://github.com/OpenIdentityPlatform/OpenAM/commit/8b02328d36bc9cd40602128a6d399d1eda9e6753
Published: 2026-09-15
Updated: 2026-09-23
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 9.2
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: Critical
EPSS: 0.00688