{"id":"CVE-2025-62491","aliases":["DEBIAN-CVE-2025-62491","EUVD-2025-34783","GHSA-3r39-xffq-r9cc","UBUNTU-CVE-2025-62491"],"status":"published","title":"Use-after-free in js_std_promise_rejection_check in QuickJS","description":"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-\u003erejected_promise_list).\n\n  *  The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.\n\n\n  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\n\n\n  *  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.\n\n\n  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\n\n\n  *  Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.\n\n\n  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","severity":{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00407,"percentile":0.35507,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-416"],"published":"2025-10-16T15:51:24Z","modified":"2026-11-09T12:49:26Z","affected":[{"source":"osv","ecosystem":"Debian:13","package":"quickjs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2025.04.26-1"]},{"source":"osv","ecosystem":"Debian:14","package":"quickjs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2025.04.26-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"quickjs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2021.03.27-1","2021.03.27-1ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"quickjs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2024.01.13-5","2025.04.26-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"quickjs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2025.04.26-1build1"]}],"products":[{"vendor":"quickjs","product":"quickjs"},{"vendor":"quickjs-ng","product":"quickjs"},{"vendor":"quickjs_project","product":"quickjs"}],"references":[{"url":"https://bellard.org/quickjs/Changelog","tags":["Release Notes","advisory","report"]},{"url":"https://issuetracker.google.com/434195203","tags":["Exploit","Issue Tracking","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-62491"},{"url":"https://github.com/advisories/GHSA-3r39-xffq-r9cc"},{"url":"https://security-tracker.debian.org/tracker/CVE-2025-62491","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2025-62491","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-62491","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2025-62491","title":"Use-after-free in js_std_promise_rejection_check in QuickJS","description":"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-\u003erejected_promise_list).\n\n  *  The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.\n\n\n  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\n\n\n  *  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.\n\n\n  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\n\n\n  *  Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.\n\n\n  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","status":"published","published":"2025-10-16T15:51:24.238Z","modified":"2025-10-16T18:04:16.529Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"high","assessor":"cna"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T14:32:55.19484Z"}],"euvd":[{"id":"EUVD-2025-34783","description":"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-\u003erejected_promise_list).\n\n  *  The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.\n\n\n  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\n\n\n  *  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.\n\n\n  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\n\n\n  *  Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.\n\n\n  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","status":"published","published":"2025-10-16T15:51:24Z","modified":"2025-10-16T18:04:16Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"high"}],"updated_at":"2026-11-02T20:31:31.065489Z"}],"ghsa":[{"id":"GHSA-3r39-xffq-r9cc","title":"A Use-After-Free (UAF) vulnerability exists in the QuickJS engine's standard library when...","description":"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-\u003erejected_promise_list).\n\n  *  The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.\n\n\n  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\n\n\n  *  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.\n\n\n  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\n\n\n  *  Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.\n\n\n  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","status":"published","published":"2025-10-16T18:30:24Z","modified":"2025-10-30T18:32:33Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T15:04:15.956958Z"}],"nvd":[{"id":"CVE-2025-62491","description":"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-\u003erejected_promise_list).\n\n  *  The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.\n\n\n  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\n\n\n  *  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.\n\n\n  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\n\n\n  *  Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.\n\n\n  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","status":"published","published":"2025-10-16T16:15:39.47Z","modified":"2026-10-19T16:10:00.26Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-416"],"updated_at":"2026-11-02T14:11:39.069866Z"}],"osv":[{"id":"CVE-2025-62491","description":"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-\u003erejected_promise_list).\n\n  *  The function js_std_promise_rejection_check attempts to iterate over the rejected_promise_list to report unhandled rejections using a standard list loop.\n\n\n  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\n\n\n  *  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.\n\n\n  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\n\n\n  *  Calling catch() internally triggers js_std_promise_rejection_tracker, which then removes and frees the current promise entry (JSRejectedPromiseEntry) from the rejected_promise_list.\n\n\n  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","status":"published","published":"2025-10-16T16:15:39.47Z","modified":"2026-04-10T05:33:05.843252Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:51.851511Z"},{"id":"DEBIAN-CVE-2025-62491","description":"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-\u003erejected_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-\u003ereason).     *  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.","status":"published","published":"2025-10-16T16:15:39.47Z","modified":"2026-10-23T17:47:30.643420674Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:47.697959Z"},{"id":"UBUNTU-CVE-2025-62491","description":"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-\u003erejected_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-\u003ereason).   *  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.","status":"published","published":"2025-10-16T16:15:00Z","modified":"2026-11-09T12:49:26.518769835Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L","level":"high"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-09T13:27:42.046613Z"}]}}