{"id":"CVE-2017-16086","aliases":["EUVD-2018-0303","GHSA-pmg9-p9r2-6q87"],"status":"published","title":"ReDoS via long UserAgent header in ua-parser","description":"ua-parser is a port of Browserscope's user agent parser. ua-parser is vulnerable to a ReDoS (Regular Expression Denial of Service) attack when given a specially crafted UserAgent header.","severity":{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-08","score":0.09102,"percentile":0.95337,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-400"],"published":"2018-06-07T02:00:00Z","modified":"2026-06-17T01:08:46Z","exploits":[{"source":"metasploit","id":"auxiliary/dos/http/ua_parser_js_redos","title":"ua-parser-js npm module ReDoS","type":"auxiliary","verified":true,"url":"https://www.rapid7.com/db/modules/auxiliary/dos/http/ua_parser_js_redos"}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"ua-parser","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.3.5"}]}]},{"source":"osv","ecosystem":"npm","package":"ua-parser","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"last_affected":"0.3.5"}]}]}],"products":[{"vendor":"hackerone","product":"ua-parser node module"},{"vendor":"ua-parser_project","product":"ua-parser"}],"references":[{"url":"https://nodesecurity.io/advisories/316","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2017-16086","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-pmg9-p9r2-6q87","tags":["advisory"]},{"url":"https://www.npmjs.com/advisories/316","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2017-16086","description":"ua-parser is a port of Browserscope's user agent parser. ua-parser is vulnerable to a ReDoS (Regular Expression Denial of Service) attack when given a specially crafted UserAgent header.","status":"published","published":"2018-06-07T02:00:00Z","modified":"2024-09-17T00:31:35.528Z","cwes":["CWE-400"],"updated_at":"2026-11-02T14:33:21.453505Z"}],"euvd":[{"id":"EUVD-2018-0303","description":"ua-parser is a port of Browserscope's user agent parser. ua-parser is vulnerable to a ReDoS (Regular Expression Denial of Service) attack when given a specially crafted UserAgent header.","status":"published","published":"2018-06-07T02:00:00Z","modified":"2024-09-17T00:31:35Z","updated_at":"2026-11-03T00:28:58.42254Z"}],"ghsa":[{"id":"GHSA-pmg9-p9r2-6q87","title":"ReDoS via long UserAgent header in ua-parser","description":"Affected versions of `ua-parser` are vulnerable to regular expression denial of service when given a specially crafted `User-Agent` header.\n\n\n## Recommendation\n\nNo patch is currently available for this vulnerability.\n\nThe best mitigation is currently to avoid using this package, using a different, functionally equivalent package such as [useragent](https://www.npmjs.com/package/useragent).","status":"published","published":"2018-07-24T19:46:37Z","modified":"2023-01-09T05:03:20Z","cwes":["CWE-400"],"updated_at":"2026-11-02T14:36:05.071174Z"}],"nvd":[{"id":"CVE-2017-16086","description":"ua-parser is a port of Browserscope's user agent parser. ua-parser is vulnerable to a ReDoS (Regular Expression Denial of Service) attack when given a specially crafted UserAgent header.","status":"published","published":"2018-06-07T02:29:01.597Z","modified":"2026-06-17T01:08:46.483Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:04:17.638656Z"}],"osv":[{"id":"GHSA-pmg9-p9r2-6q87","title":"ReDoS via long UserAgent header in ua-parser","description":"Affected versions of `ua-parser` are vulnerable to regular expression denial of service when given a specially crafted `User-Agent` header.\n\n\n## Recommendation\n\nNo patch is currently available for this vulnerability.\n\nThe best mitigation is currently to avoid using this package, using a different, functionally equivalent package such as [useragent](https://www.npmjs.com/package/useragent).","status":"published","published":"2018-07-24T19:46:37Z","modified":"2023-11-08T03:59:04.001707Z","cwes":["CWE-400"],"updated_at":"2026-11-02T15:46:53.244788Z"}]}}