{"answers":{"affected":"2 open source packages ship an affected version, including @nyariv/sandboxjs. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25520 exists.","fix":"Upgrade @nyariv/sandboxjs to 0.8.29 or later.","what":"CVE-2026-25520 is a critical code injection vulnerability in nyariv SandboxJS, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-25520 and fix it if it is affected.\n\nWhat it is: CVE-2026-25520 is a critical code injection vulnerability in nyariv SandboxJS, published on 6 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25520 exists.\n\nAffected packages and fixed versions:\n- @nyariv/sandboxjs (npm): affected all versions; fixed in 0.8.29\n- @nyariv/sandboxjs (npm): affected all versions; fixed in 0.8.29\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-2026-25520/ (Markdown: https://insights.sbomify.com/CVE-2026-25520/index.md)","id":"CVE-2026-25520","markdown":"https://insights.sbomify.com/CVE-2026-25520/index.md","name":"CVE-2026-25520","record":{"aliases":["GHSA-58jh-xv4v-pcx4"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"JavaScript sandboxing library","requires_auth":"none","summary":"Attackers can escape the SandboxJS sandbox to execute arbitrary code on the host by accessing the Function constructor via unreturned values.","user_interaction":"not_required","vuln_class":"code_injection"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"sandboxjs","vendor":"nyariv"}],"cvss":{"score":10,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-74","name":"Improper Neutralization of Special Elements in Output Used by a Downstream Component"}],"description":"SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, The return values of functions aren't wrapped. Object.values/Object.entries can be used to get an Array containing the host's Function constructor, by using Array.prototype.at you can obtain the hosts Function constructor, which can be used to execute arbitrary code outside of the sandbox. This vulnerability is fixed in 0.8.29.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"SandboxJS has a Sandbox Escape","id":"CVE-2026-25520","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"code_injection","year":"2026"},"n_packages":2,"n_references":2,"next":{"headline":"Locutus is vulnerable to Prototype Pollution","id":"CVE-2026-25521"},"packages":[{"ecosystem":"npm","fixed":["0.8.29"],"introduced":["0"],"last_affected":[],"package":"@nyariv/sandboxjs","purl":null,"source":"GHSA-58jh-xv4v-pcx4"},{"ecosystem":"npm","fixed":["0.8.29"],"introduced":["0"],"last_affected":[],"package":"@nyariv/sandboxjs","purl":"pkg:npm/%40nyariv/sandboxjs","source":"GHSA-58jh-xv4v-pcx4"}],"prev":{"headline":"OpenSlides has incorrect access control vulnerability in authentication service","id":"CVE-2026-25519"},"products":["SandboxJS"],"published":"2026-02-06","related":[{"cvss_score":10,"headline":"SandboxJS: Sandbox escape via Function.caller leakage of internal call op","id":"CVE-2026-43898","kev_date_added":null,"published":"2026-05-28"},{"cvss_score":10,"headline":"SandboxJS: Sandbox integrity escape","id":"CVE-2026-34208","kev_date_added":null,"published":"2026-04-06"},{"cvss_score":10,"headline":"SandboxJS has a Sandbox Escape","id":"CVE-2026-26954","kev_date_added":null,"published":"2026-03-13"},{"cvss_score":10,"headline":"SandboxJS has a Sandbox Escape via Prototype Whitelist Bypass and Host Prototype Pollution","id":"CVE-2026-25586","kev_date_added":null,"published":"2026-02-06"},{"cvss_score":10,"headline":"SandboxJS has a Sandbox Escape","id":"CVE-2026-25587","kev_date_added":null,"published":"2026-02-06"},{"cvss_score":10,"headline":"SandboxJS has a sandbox escape via TOCTOU bug on keys in property accesses","id":"CVE-2026-25641","kev_date_added":null,"published":"2026-02-06"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"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":"yes","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-02-06","vendors":["nyariv"]},"summary":"Attackers can escape the SandboxJS sandbox to execute arbitrary code on the host by accessing the Function constructor via unreturned values.","url":"https://insights.sbomify.com/CVE-2026-25520/"}