CVE-2010-2477 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in paste. A fix is available for paste — see the affected versions and patch details below.
Paste is vulnerable to Cross-site Scripting via vectors involving a 404 status code
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
pasteReal-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
Multiple cross-site scripting (XSS) vulnerabilities in the paste.httpexceptions implementation in Paste before 1.7.4 allow remote attackers to inject arbitrary web script or HTML via vectors involving a 404 status code, related to (1) paste.urlparser.StaticURLParser, (2) paste.urlparser.PkgResourcesParser, (3) paste.urlmap.URLMap, and (4) HTTPNotFound.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | paste | all versions | 1.7.4pip install --upgrade 'paste==1.7.4' |
Affected Products
pastepythonpasteDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for paste, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update paste to 1.7.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2010-2477 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.
Frequently Asked Questions
Is CVE-2010-2477 in your dependencies?
Find it across PyPI, including transitive dependencies.