CVE-2025-12758 — validator
Fix: validatorjs/validator.js#2616CVE-2025-12758 is a CWE-792 vulnerability in validator. A fix is available for validator — see the affected versions and patch details below.
Validator is Vulnerable to Incomplete Filtering of One or More Instances of Special Elements
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-12758.
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.
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 the package validator before 13.15.22 are vulnerable to Incomplete Filtering of One or More Instances of Special Elements in the isLength() function that does not take into account Unicode variation selectors (\uFE0F, \uFE0E) appearing in a sequence which lead to improper string length calculation. This can lead to an application using isLength for input validation accepting strings significantly longer than intended, resulting in issues like data truncation in databases, buffer overflows in other system components, or denial-of-service.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | validator | all versions | 13.15.22npm install validator@13.15.22 |
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 13.15.22 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-12758 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-2025-12758 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-12758. 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-2025-12758 in your dependencies?
O3 Security finds CVE-2025-12758 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.