{"id":"CVE-2021-43787","aliases":["EUVD-2021-2408","GHSA-wx69-rvg3-x7fc"],"status":"published","title":"XSS via prototype pollution","description":"Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.","severity":{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.01317,"percentile":0.71035,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1321","CWE-79"],"published":"2021-11-29T19:30:11Z","modified":"2026-10-20T10:55:03Z","fixes":[{"ecosystem":"npm","package":"nodebb","fixed_in":["1.18.5"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"nodebb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.15.0"},{"fixed":"1.18.5"}]}]},{"source":"osv","ecosystem":"npm","package":"nodebb","ranges":[{"type":"SEMVER","events":[{"introduced":"1.15.0"},{"fixed":"1.18.5"}]}]}],"products":[{"vendor":"nodebb","product":"nodebb"}],"references":[{"url":"https://github.com/NodeBB/NodeBB/security/advisories/GHSA-wx69-rvg3-x7fc","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/NodeBB/NodeBB/commit/1783f918bc19568f421473824461ff2ed7755e4c","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/NodeBB/NodeBB/releases/tag/v1.18.5","tags":["x_refsource_MISC","x_transferred","Patch","Release Notes","Third Party Advisory","fix","web"]},{"url":"https://blog.sonarsource.com/nodebb-remote-code-execution-with-one-shot/","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory","evidence"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43787","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-wx69-rvg3-x7fc"},{"url":"https://blog.sonarsource.com/nodebb-remote-code-execution-with-one-shot","tags":["web"]},{"url":"https://github.com/NodeBB/NodeBB","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2021-43787","title":"XSS via prototype pollution","description":"Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.","status":"published","published":"2021-11-29T19:30:11Z","modified":"2024-08-04T04:03:08.858Z","cvss":[{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"cna"}],"cwes":["CWE-79","CWE-1321"],"updated_at":"2026-11-02T14:32:56.689433Z"}],"euvd":[{"id":"EUVD-2021-2408","description":"Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.","status":"published","published":"2021-11-29T19:30:11Z","modified":"2024-08-04T04:03:08Z","cvss":[{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical"}],"updated_at":"2026-11-03T03:24:13.772922Z"}],"ghsa":[{"id":"GHSA-wx69-rvg3-x7fc","title":"XSS via prototype pollution in NodeBB ","description":"### Impact\nA prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report.\n\n### Patches\nThe vulnerability has been patched as of v1.18.5.\n\n### Workarounds\nCherry-pick commit hash 1783f918bc19568f421473824461ff2ed7755e4c to receive this patch in lieu of a full upgrade.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Email us at [security@nodebb.org](mailto:security@nodebb.org)\n","status":"published","published":"2021-11-30T22:21:01Z","modified":"2023-01-31T05:06:32Z","cvss":[{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:36:29.957996Z"}],"nvd":[{"id":"CVE-2021-43787","description":"Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.","status":"published","published":"2021-11-29T20:15:08.19Z","modified":"2026-06-17T04:11:26.35Z","cvss":[{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"secondary"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-79","CWE-1321"],"updated_at":"2026-11-02T14:07:01.811115Z"}],"osv":[{"id":"CVE-2021-43787","description":"Nodebb is an open source Node.js based forum software. In affected versions a prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report. The vulnerability has been patched as of v1.18.5. Users are advised to upgrade as soon as possible.","status":"published","published":"2021-11-29T20:15:08.19Z","modified":"2026-10-20T10:55:03.2013933Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:21.877444Z"},{"id":"GHSA-wx69-rvg3-x7fc","title":"XSS via prototype pollution in NodeBB ","description":"### Impact\nA prototype pollution vulnerability in the uploader module allowed a malicious user to inject arbitrary data (i.e. javascript) into the DOM, theoretically allowing for an account takeover when used in conjunction with a path traversal vulnerability disclosed at the same time as this report.\n\n### Patches\nThe vulnerability has been patched as of v1.18.5.\n\n### Workarounds\nCherry-pick commit hash 1783f918bc19568f421473824461ff2ed7755e4c to receive this patch in lieu of a full upgrade.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Email us at [security@nodebb.org](mailto:security@nodebb.org)\n","status":"published","published":"2021-11-30T22:21:01Z","modified":"2026-07-08T06:28:24.545510977Z","cvss":[{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:46:59.131095Z"}]}}