GHSA-xxfx-w2rw-gh63 is a medium-severity (CVSS 5.4) Cross-site Scripting (XSS) vulnerability in github.com/csaf-poc/csaf_distribution. A fix is available for github.com/csaf-poc/csaf_distribution — see the affected versions and patch details below.
csaf-poc/csaf_distribution Cross-site Scripting vulnerability
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-xxfx-w2rw-gh63.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-xxfx-w2rw-gh63 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/csaf-poc/csaf_distributionReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
The csaf_provider package before 0.8.2 allows XSS via a crafted CSAF document uploaded as text/html. The endpoint upload allows valid CSAF advisories (JSON format) to be uploaded with Content-Type text/html and filenames ending in .html. When subsequently accessed via web browser, these advisories are served and interpreted as HTML pages. Such uploaded advisories can contain JavaScript code that will execute within the browser context of users inspecting the advisory.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/csaf-poc/csaf_distribution | all versions | 0.8.2go get github.com/csaf-poc/csaf_distribution@v0.8.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/csaf-poc/csaf_distribution, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/csaf-poc/csaf_distribution to 0.8.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xxfx-w2rw-gh63 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-xxfx-w2rw-gh63 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-xxfx-w2rw-gh63. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-xxfx-w2rw-gh63 in your dependencies?
O3 Security finds GHSA-xxfx-w2rw-gh63 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.