{"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-2026-23830 exists.","fix":"Upgrade @nyariv/sandboxjs to 0.8.26 or later.","what":"CVE-2026-23830 is a critical code injection vulnerability in nyariv SandboxJS, published on 27 Jan 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-2026-23830 and fix it if it is affected.\n\nWhat it is: CVE-2026-23830 is a critical code injection vulnerability in nyariv SandboxJS, published on 27 Jan 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-2026-23830 exists.\n\nAffected packages and fixed versions:\n- @nyariv/sandboxjs (npm): affected all versions; fixed in 0.8.26\n- @nyariv/sandboxjs (npm): affected all versions; fixed in 0.8.26\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-2026-23830/ (Markdown: https://insights.sbomify.com/CVE-2026-23830/index.md)","id":"CVE-2026-23830","markdown":"https://insights.sbomify.com/CVE-2026-23830/index.md","name":"CVE-2026-23830","record":{"aliases":["GHSA-wxhw-j4hc-fmq6"],"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 by accessing the unprotected AsyncFunction constructor, leading to remote code execution on the host.","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-94","name":"Improper Control of Generation of Code"},{"id":"CWE-913","name":"Improper Control of Dynamically-Managed Code Resources"},{"id":"CWE-693","name":"Protection Mechanism Failure"}],"description":"SandboxJS is a JavaScript sandboxing library. Versions prior to 0.8.26 have a sandbox escape vulnerability due to `AsyncFunction` not being isolated in `SandboxFunction`. The library attempts to sandbox code execution by replacing the global `Function` constructor with a safe, sandboxed version (`SandboxFunction`). This is handled in `utils.ts` by mapping `Function` to `sandboxFunction` within a map used for lookups. However, before version 0.8.26, the library did not include mappings for `AsyncFunction`, `GeneratorFunction`, and `AsyncGeneratorFunction`. These constructors are not global properties but can be accessed via the `.constructor` property of an instance (e.g., `(async () =\u003e {}).constructor`). In `executor.ts`, property access is handled. When code running inside the sandbox accesses `.constructor` on an async function (which the sandbox allows creating), the `executor` retrieves the property value. Since `AsyncFunction` was not in the safe-replacement map, the `executor` returns the actual native host `AsyncFunction` constructor. Constructors for functions in JavaScript (like `Function`, `AsyncFunction`) create functions that execute in the global scope. By obtaining the host `AsyncFunction` constructor, an attacker can create a new async function that executes entirely outside the sandbox context, bypassing all restrictions and gaining full access to the host environment (Remote Code Execution). Version 0.8.26 patches this vulnerability.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":"2026-01-28","github_poc":1,"max_poc_stars":1,"metasploit":0,"nuclei":0,"refs":[{"date":"2026-01-28T12:32:07Z","kind":"github_poc","ref":"https://github.com/Galaxy-sc/CVE-2026-23830-SandBreak","stars":1,"title":null}],"tier":"weaponised"},"has_fix":true,"headline":"SandboxJS has Sandbox Escape via Unprotected AsyncFunction Constructor","id":"CVE-2026-23830","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":"Rekor COSE v0.0.1 Canonicalize crashes when passed empty Message","id":"CVE-2026-23831"},"packages":[{"ecosystem":"npm","fixed":["0.8.26"],"introduced":["0"],"last_affected":[],"package":"@nyariv/sandboxjs","purl":null,"source":"GHSA-wxhw-j4hc-fmq6"},{"ecosystem":"npm","fixed":["0.8.26"],"introduced":["0"],"last_affected":[],"package":"@nyariv/sandboxjs","purl":"pkg:npm/%40nyariv/sandboxjs","source":"GHSA-wxhw-j4hc-fmq6"}],"prev":{"headline":"Mailpit has SMTP Header Injection via Regex Bypass","id":"CVE-2026-23829"},"products":["SandboxJS"],"published":"2026-01-27","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","id":"CVE-2026-25520","kev_date_added":null,"published":"2026-02-06"},{"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)"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":"yes","exploitation":"poc","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-01-28","vendors":["nyariv"]},"summary":"Attackers can escape the SandboxJS sandbox by accessing the unprotected AsyncFunction constructor, leading to remote code execution on the host.","url":"https://insights.sbomify.com/CVE-2026-23830/"}