{"id":"UBUNTU-CVE-2021-21317","details":"uap-core in an open-source npm package which contains the core of BrowserScope's original user agent string parser. In uap-core before version 0.11.0, some regexes are vulnerable to regular expression denial of service (REDoS) due to overlapping capture groups. This allows remote attackers to overload a server by setting the User-Agent header in an HTTP(S) request to maliciously crafted long strings. This is fixed in version 0.11.0. Downstream packages such as uap-python, uap-ruby etc which depend upon uap-core follow different version schemes.","modified":"2026-05-20T16:04:44.895078594Z","published":"2021-02-16T18:15:00Z","upstream":["CVE-2021-21317"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-21317"},{"type":"REPORT","url":"https://github.com/ua-parser/uap-core/security/advisories/GHSA-p4pj-mg4r-x6v4"},{"type":"REPORT","url":"https://www.npmjs.com/package/uap-core"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-21317"}],"affected":[{"package":{"name":"uap-core","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/uap-core?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["20190213-2"],"ecosystem_specific":{"binaries":[{"binary_name":"uap-core","binary_version":"20190213-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-21317.json"}},{"package":{"name":"uap-core","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/uap-core?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:0.12.0-1","1:0.13.0-1","1:0.14.0-1","1:0.15.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"uap-core","binary_version":"1:0.15.0-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-21317.json"}},{"package":{"name":"uap-core","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/uap-core?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:0.18.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1:0.18.0-1","binary_name":"uap-core"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-21317.json"}},{"package":{"name":"uap-core","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/uap-core?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:0.18.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1:0.18.0-1","binary_name":"uap-core"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-21317.json"}},{"package":{"name":"uap-core","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/uap-core?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:0.18.0-1","1:0.18.0-1build1"],"ecosystem_specific":{"binaries":[{"binary_version":"1:0.18.0-1build1","binary_name":"uap-core"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-21317.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"Ubuntu","score":"medium"}]}