CVE-2013-7454 — validator
MEDIUMCVE-2013-7454 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in validator. A fix is available for validator — see the affected versions and patch details below.
Multiple XSS Filter Bypasses in validator
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-2013-7454 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 377,636 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
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
validatornpmDescription
Versions of validator prior to 1.1.0 are affected by several cross-site scripting vulnerabilities due to bypasses discovered in the blacklist-based filter.
Proof of Concept
Various inputs that could bypass the filter were discovered:
Improper parsing of nested tags:
<s <onmouseover="alert(1)"> <;s onmouseover="alert(1)">This is a test</s>
Incomplete filtering of javascript: URIs:
<a href="javascriptJ a V a S c R iPt::alert(1)" "<s>">test</a>
UI Redressing:
<div style="z-index: 9999999; background-color: green; width: 100%; height: 100%">
<h1>You have won</h1>Please click the link and enter your login details:
<a href="http://example.com/">http://good.com</a>
</div>
Bypass via Nested Forbidden Strings:
<scrRedirecRedirect 302t 302ipt type="text/javascript">prompt(1);</scrRedirecRedirect 302t 302ipt>
Additional bypasses were discovered by Krzysztof Kotowicz in 2012 when auditing CodeIgniter's XSS filtering function, which this code was based off of.
Recommendation
If you are a developer currently using the xss filter function from the validator package, you should consider replacing it with the escape filter function from the same package. This function replaces all instances of angle brackets (<, >), ampersands, and quotation marks, so no HTML tags will be processed.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | validator | all versions | 1.1.0npm install validator@1.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for validator, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update validator to 1.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2013-7454 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 CVE-2013-7454 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2013-7454. 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-2013-7454 in your dependencies?
O3 Security finds CVE-2013-7454 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.