{"answers":{"affected":"It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-62491 exists.","fix":"No fix has been published for CVE-2025-62491 yet. Limit exposure of the affected software until one is available.","what":"CVE-2025-62491 is a high-severity use after free vulnerability in QuickJS, published on 16 Oct 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2025-62491 and fix it if it is affected.\n\nWhat it is: CVE-2025-62491 is a high-severity use after free vulnerability in QuickJS, published on 16 Oct 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-62491 exists.\n\nAffected product: QuickJS. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2025-62491/ (Markdown: https://insights.sbomify.com/CVE-2025-62491/index.md)","id":"CVE-2025-62491","markdown":"https://insights.sbomify.com/CVE-2025-62491/index.md","name":"CVE-2025-62491","record":{"aliases":["DEBIAN-CVE-2025-62491","GHSA-3r39-xffq-r9cc","UBUNTU-CVE-2025-62491"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["code_execution","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"JavaScript engine library","requires_auth":"none","summary":"A use-after-free in QuickJS allows attackers to execute arbitrary code or cause denial of service via malicious JavaScript promise rejection handlers.","user_interaction":"required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Google","cpe":[{"product":"quickjs","vendor":"quickjs_project"}],"cvss":{"score":8.8,"severity":"high","source":"cna","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","version":"4.0"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"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  *  The reason for a promise rejection is processed inside the loop, including calling js_std_dump_error1(ctx, rp-\u003ereason).\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  *  The malicious custom getter can execute JavaScript code that calls catch() on the same rejected promise being processed.\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  *  Since the list iteration continues using the now-freed memory pointer (el), the subsequent loop access results in a Use-After-Free condition.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":false,"headline":"Use-after-free in js_std_promise_rejection_check in QuickJS","id":"CVE-2025-62491","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"use_after_free","year":"2025"},"n_packages":0,"n_references":2,"next":{"headline":"Heap out-of-bounds read in js_typed_array_indexOf in QuickJS","id":"CVE-2025-62492"},"packages":[],"prev":{"headline":"Use-after-free in js_print_object in QuickJS","id":"CVE-2025-62490"},"products":["QuickJS"],"published":"2025-10-16","related":[{"cvss_score":8.8,"headline":"Use-after-free in js_print_object in QuickJS","id":"CVE-2025-62490","kev_date_added":null,"published":"2025-10-16"},{"cvss_score":7.5,"headline":"Denial of service in n/a","id":"CVE-2025-69654","kev_date_added":null,"published":"2026-03-06"},{"cvss_score":7.5,"headline":"Null dereference in n/a","id":"CVE-2023-48183","kev_date_added":null,"published":"2024-04-23"},{"cvss_score":7.5,"headline":"Denial of service in n/a","id":"CVE-2023-31922","kev_date_added":null,"published":"2023-05-12"},{"cvss_score":7.5,"headline":"Memory corruption in n/a","id":"CVE-2020-22876","kev_date_added":null,"published":"2021-07-13"},{"cvss_score":7.1,"headline":"Type confusion in string addition in QuickJS","id":"CVE-2025-62494","kev_date_added":null,"published":"2025-10-16"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2025-10-16","vendors":["QuickJS"]},"summary":"A use-after-free in QuickJS allows attackers to execute arbitrary code or cause denial of service via malicious JavaScript promise rejection handlers.","url":"https://insights.sbomify.com/CVE-2025-62491/"}