# GHSA-rrfw-hg9m-j47h: Signature Validation Bypass

> An authentication bypass in the goxmldsig library allows attackers to forge SAML assertions, potentially leading to unauthorized access.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 May 2021

## What is GHSA-rrfw-hg9m-j47h?

GHSA-rrfw-hg9m-j47h is an authentication bypass vulnerability in github.com/russellhaering/goxmldsig, published on 24 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### Impact

An authentication bypass exists in the [goxmldsig](https://github.com/russellhaering/goxmldsig/security/advisories/GHSA-q547-gmf8-8jr7) this library uses to determine if SAML assertions are genuine. An attacker could craft a SAML response that would appear to be valid but would not have been genuinely issued by the IDP.

### Patches

Version 0.4.2 bumps the dependency which should fix the issue.

### For more information

Please see [the advisory in goxmldsig](https://github.com/russellhaering/goxmldsig/security/advisories/GHSA-q547-gmf8-8jr7)

## Credits

The original vulnerability was discovered by @jupenur. Thanks to @russellhaering for the heads up.

## Which versions are affected by GHSA-rrfw-hg9m-j47h?

2 open source packages ship an affected version, including github.com/russellhaering/goxmldsig.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/russellhaering/goxmldsig` | Go | All versions | 0.4.2 |
| `github.com/russellhaering/goxmldsig` | Go | All versions | 0.4.2 |

## How do I fix GHSA-rrfw-hg9m-j47h?

Upgrade github.com/russellhaering/goxmldsig to 0.4.2 or later.

## Is GHSA-rrfw-hg9m-j47h being exploited?

There is no known exploitation of GHSA-rrfw-hg9m-j47h in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-rrfw-hg9m-j47h and fix it if it is affected.

What it is: GHSA-rrfw-hg9m-j47h is an authentication bypass vulnerability in github.com/russellhaering/goxmldsig, published on 24 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-rrfw-hg9m-j47h in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/russellhaering/goxmldsig (Go): affected all versions; fixed in 0.4.2
- github.com/russellhaering/goxmldsig (Go): affected all versions; fixed in 0.4.2

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/GHSA-rrfw-hg9m-j47h/ (Markdown: https://insights.sbomify.com/GHSA-rrfw-hg9m-j47h/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-rrfw-hg9m-j47h

---
From sbomify Insights: https://insights.sbomify.com/GHSA-rrfw-hg9m-j47h/
Summaries are generated and may contain mistakes; the official description above is the record.