---
title: "CVE-2026-45051: OpenAM: Pre-auth RCE via Java Deserialization in WebAuthn Authenticator Storage"
url: https://erroneo.us/security/cve/CVE-2026-45051/
description: "CVE-2026-45051 (org.openidentityplatform.openam:openam-auth-webauthn (Maven)): Open Access Management (OpenAM) is an access management solution. Prior to…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-09-15
date_modified: 2026-09-15
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-45051"
kev: false
cvss: 9.2
epss: 0.00688
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-45051: OpenAM: Pre-auth RCE via Java Deserialization in WebAuthn Authenticator Storage

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.7% , percentile 52: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 52% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes org.openidentityplatform.openam:openam-auth-webauthn (Maven) <= 16.0.6, fixed in 16.1.1 . Check your lockfile, including transitive dependencies.

## What it is

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.

## Affected packages

- Maven `org.openidentityplatform.openam:openam-auth-webauthn` <= 16.0.6 → fixed: 16.1.1

## Affected products (CVE record)

- OpenIdentityPlatform OpenAM: < 16.1.1

## Severity

- GitHub_M CVSS 4.0: 9.2 `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`
- GitHub CVSS 4.0: 9.2 `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`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.69% probability of exploitation activity in the next 30 days; percentile 52.

## Sources

- [GitHub Advisory GHSA-6c99-87fr-6q7r](https://github.com/advisories/GHSA-6c99-87fr-6q7r)
- [CVE.org record CVE-2026-45051](https://www.cve.org/CVERecord?id=CVE-2026-45051)
- [NVD entry CVE-2026-45051](https://nvd.nist.gov/vuln/detail/CVE-2026-45051)
- [github.com](https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-6c99-87fr-6q7r)
- [github.com](https://github.com/OpenIdentityPlatform/OpenAM/commit/8b02328d36bc9cd40602128a6d399d1eda9e6753)
- [github.com](https://github.com/OpenIdentityPlatform/OpenAM/releases/tag/16.1.1)

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Source page: https://erroneo.us/security/cve/CVE-2026-45051/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt