GHSA-f7f6-9jq7-3rqj
estree-util-value-to-estree allows prototype pollution in generated ESTree
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.
Blast Radius
estree-util-value-to-estreeReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Impact
When generating an ESTree from a value with a property named __proto__, valueToEstree would generate an object that specifies a prototype instead.
Example:
import { generate } from 'astring'
import { valueToEstree } from 'estree-util-value-to-estree'
const estree = valueToEstree({
['__proto__']: {}
})
const code = generate(estree)
console.log(code)
Output:
{
"__proto__": {}
}
Patches
This was fixed in version 3.3.3.
Workarounds
If you control the input, don’t specify a property named __proto__. If you don’t control the output, strip any properties named __proto__ before passing it to valueToEstree.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | estree-util-value-to-estree | all versions | 3.3.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for estree-util-value-to-estree. 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 estree-util-value-to-estree to 3.3.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f7f6-9jq7-3rqj 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 GHSA-f7f6-9jq7-3rqj 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 GHSA-f7f6-9jq7-3rqj. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-f7f6-9jq7-3rqj in your dependencies?
O3 detects GHSA-f7f6-9jq7-3rqj across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.