CVE-2016-4807 — web2py
MEDIUMCVE-2016-4807 is a medium-severity (CVSS 4.8) Cross-site Scripting (XSS) vulnerability in web2py. 3 public exploit references exist, so weaponization risk is real. No vendor fix is recorded yet; mitigation options are listed below.
Web2py Reflected XSS vulnerability
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
CVE-2016-4807 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 377,333 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
web2pyReal-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
Web2py versions 2.14.5 and below was affected by Reflected XSS vulnerability, which allows an attacker to perform an XSS attack on logged in user (admin).
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | web2py | all versions | No fix |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Web2py 2.14.5 - Multiple Vulnerabilities
by Narendra Bhati · May 16, 2016
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for web2py, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of web2py has shipped for CVE-2016-4807 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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 CVE-2016-4807 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2016-4807. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2016-4807 in your dependencies?
O3 Security finds CVE-2016-4807 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.