GHSA-9c6g-qpgj-rvxw is a medium-severity (CVSS 5.9) Cross-site Scripting (XSS) vulnerability in streamlit. A fix is available for streamlit — see the affected versions and patch details below.
Streamlit publishes previously-patched 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-9c6g-qpgj-rvxw.
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-9c6g-qpgj-rvxw 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 377,166 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
streamlitReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Synopsis: Streamlit open source publicizes a prior security fix implemented in 2021. The vulnerability affected Streamlit versions between 0.63.0 and 0.80.0 (inclusive) and was patched on April 21, 2021. If you are using Streamlit with version before 0.63.0 or after 0.80.0, no action is required.
1. Impacted Products
Streamilt Open Source versions between 0.63.0 and 0.80.0.
2. Introduction
On April 21, 2021, Streamlit merged a patch that fixed a cross-site scripting (XSS) vulnerability in the Streamlit open source library, without an associated public advisory. The vulnerability affected Streamlit versions between 0.63.0 and 0.80.0 (inclusive), which are no longer supported. We recommend using the latest version of our library, but so long as you are not using an affected Streamlit version, no action is required.
3. Cross Site Scripting Vulnerability
3.1 Description
On April 20, 2021, Streamlit was informed via our support forum about a XSS vulnerability in the open source library. We fixed and merged a patch remediating the vulnerability on April 21st, 2021. The issue was determined to be in the moderate severity range with a maximum CVSSv3 base score of 5.9
3.2 Scenarios and attack vector(s)
Users of hosted Streamlit app(s) were vulnerable to a reflected XSS vulnerability. An attacker could craft a malicious URL with Javascript payloads to a Streamlit app. The attacker could then trick the user into visiting the malicious URL and, if successful, the server would render the malicious javascript payload as-is, leading to an XSS.
3.3 Our response
Streamlit fixed and merged a patch for this vulnerability on April 21, 2021. The vulnerability was fixed within 24hrs of notification to Streamlit.
3.4 Resolution
The vulnerability has been fixed in all Streamlit versions released since April 21, 2021. The affected versions – those between 0.63.0 and 0.80.0 (inclusive) – are no longer supported. We recommend always using supported versions of the Streamlit open source library. Version 1.19.0 is current as of this advisory.
4. Contact
Please contact [email protected] if you have any questions regarding this advisory. If you discover a security vulnerability in one of our products or websites, please report the issue to HackerOne. For more information, please see our Vulnerability Disclosure Policy.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | streamlit | ≥ 0.63.0&&< 0.81.0 | 0.81.0pip install --upgrade 'streamlit==0.81.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for streamlit, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update streamlit to 0.81.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9c6g-qpgj-rvxw is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-9c6g-qpgj-rvxw can be triaged on real exposure rather than presence alone.
Tailored to GHSA-9c6g-qpgj-rvxw. 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-9c6g-qpgj-rvxw in your dependencies?
O3 Security finds GHSA-9c6g-qpgj-rvxw across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.