CVE-2024-43357
HIGHJavaScript specification issue may lead to type confusion and pointer dereference in implementations
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.
Description
ECMA-262 is the language specification for the scripting language ECMAScript. A problem in the ECMAScript (JavaScript) specification of async generators, introduced by a May 2021 spec refactor, may lead to mis-implementation in a way that could present as a security vulnerability, such as type confusion and pointer dereference.
The internal async generator machinery calls regular promise resolver functions on IteratorResult ({ done, value }) objects that it creates, assuming that the IteratorResult objects will not be then-ables. Unfortunately, these IteratorResult objects inherit from Object.prototype, so these IteratorResult objects can be made then-able, triggering arbitrary behaviour, including re-entering the async generator machinery in a way that violates some internal invariants.
The ECMAScript specification is a living standard and the issue has been addressed at the time of this advisory's public disclosure. JavaScript engine implementors should refer to the latest specification and update their implementations to comply with the AsyncGenerator section.
References
- https://github.com/tc39/ecma262/commit/1e24a286d0a327d08e1154926b3ee79820232727
- https://bugzilla.mozilla.org/show_bug.cgi?id=1901411
- https://github.com/boa-dev/boa/security/advisories/GHSA-f67q-wr6w-23jq
- https://bugs.webkit.org/show_bug.cgi?id=275407
- https://issues.chromium.org/issues/346692561
- https://www.cve.org/CVERecord?id=CVE-2024-7652
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. 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.
Remediation status
No patched version of the affected component has shipped for CVE-2024-43357 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 pinpoints whether CVE-2024-43357 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-2024-43357. 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-2024-43357 in your dependencies?
O3 detects CVE-2024-43357 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.