CVE-2026-62263 OpenAM: WebAuthn Java deserialization RCE via ObjectInputFilter depth>1 bypass
Pre-authentication attackers can achieve remote code execution in OpenAM by bypassing deserialization filters in WebAuthn authentication.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-62263?
CVE-2026-62263 is a critical unsafe deserialization vulnerability in OpenIdentityPlatform OpenAM, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Open Access Management (OpenAM) is an access management solution. Prior to 16.1.2, WebAuthnAuthentication.deserialize applies an ObjectInputFilter that allows every serialized object at depth greater than 1 and therefore constrains only an AuthenticatorImpl root object. A pre-authentication attacker can supply a userHandle whose serialized graph has a valid AuthenticatorImpl root and a nested gadget class, causing readObject or readResolve execution before the cast and assertion verification when a usable gadget is on the classpath. This bypasses the incomplete remediation for the earlier WebAuthn deserialization vulnerability. This issue is fixed in version 16.1.2.
Weakness: CWE-502
Which versions are affected by CVE-2026-62263?
2 open source packages ship an affected version, including org.openidentityplatform.openam:openam-auth-webauthn.
| Package | Affected | Fixed in |
|---|---|---|
org.openidentityplatform.openam:openam-auth-webauthn Maven | All versions | 16.1.2 |
org.openidentityplatform.openam:openam-auth-webauthn Maven | All versions | 16.1.2 |
How do I fix CVE-2026-62263?
Upgrade org.openidentityplatform.openam:openam-auth-webauthn to 16.1.2 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-62263 being exploited?
There is no known exploitation of CVE-2026-62263 in the wild and no public exploit code.
Sources
Also known as GHSA-gf8h-gq53-288j, UBUNTU-CVE-2026-62263.