# CVE-2026-15556: Picketlink-federation: picketlink saml 2.0 auth bypass via missing assertions

> Attackers can forge SAML responses to bypass authentication and gain unauthorized access with any role in JBoss EAP applications.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Aug 2026
- **Updated:** 26 Oct 2026
- **Also known as:** GHSA-vw9v-mpfh-qwg3

## What is CVE-2026-15556?

CVE-2026-15556 is a high-severity authentication bypass vulnerability in Red Hat JBoss Enterprise Application Platform 7, published on 11 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A flaw was found in Picketlink's SP signature validation; a SAML response containing zero assertion elements matching the signature check can allow an attacker to forge a SAML response and auth as any principal with any roles on the protected application.

Weakness: CWE-347 (Improper Verification of Cryptographic Signature)

## Which versions are affected by CVE-2026-15556?


## How do I fix CVE-2026-15556?

Apply the vendor's patch.

## Is CVE-2026-15556 being exploited?

There is no known exploitation of CVE-2026-15556 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-15556 and fix it if it is affected.

What it is: CVE-2026-15556 is a high-severity authentication bypass vulnerability in Red Hat JBoss Enterprise Application Platform 7, published on 11 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-15556 in the wild and no public exploit code.

Affected product: Red Hat JBoss Enterprise Application Platform 7. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-15556/ (Markdown: https://insights.sbomify.com/CVE-2026-15556/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-15556
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-15556
- OSV: https://osv.dev/vulnerability/CVE-2026-15556

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-15556/
Summaries are generated and may contain mistakes; the official description above is the record.