CVE-2026-23957
HIGHCVE-2026-23957 is a high-severity (CVSS 7.5) CWE-770 vulnerability in seroval. O3 Security confirms whether CVE-2026-23957 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
seroval is vulnerable to Denial of Service via array serialization
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
serovalnpmDescription
seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. In versions 1.4.0 and below, overriding encoded array lengths by replacing them with an excessively large value causes the deserialization process to significantly increase processing time. This issue has been fixed in version 1.4.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | seroval | all versions | 1.4.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for seroval. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update seroval to 1.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-23957 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 pinpoints whether CVE-2026-23957 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-23957. 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-2026-23957 in your dependencies?
O3 detects CVE-2026-23957 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.