A Use-After-Free (UAF) vulnerability exists in the QuickJS engine's standard library when iterating over the global list of unhandled rejected promises (ts->rejected_promise_list).
* The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.
* The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp->reason).
* If the promise rejection reason is an Error object that defines a custom property getter (e.g., via Object.defineProperty), this getter is executed during the error dumping process.
* The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.
* Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.
* Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.
References
| Link | Resource |
|---|---|
| https://bellard.org/quickjs/Changelog | Release Notes |
| https://issuetracker.google.com/434195203 | Exploit Issue Tracking |
Configurations
History
30 Oct 2025, 16:27
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://bellard.org/quickjs/Changelog - Release Notes | |
| References | () https://issuetracker.google.com/434195203 - Exploit, Issue Tracking | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 8.8 |
| First Time |
Quickjs Project quickjs
Quickjs Project |
|
| CPE | cpe:2.3:a:quickjs_project:quickjs:*:*:*:*:*:*:*:* |
16 Oct 2025, 16:15
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2025-10-16 16:15
Updated : 2025-10-30 16:27
NVD link : CVE-2025-62491
Mitre link : CVE-2025-62491
CVE.ORG link : CVE-2025-62491
JSON object : View
Products Affected
quickjs_project
- quickjs
CWE
CWE-416
Use After Free