{"id":"USN-4906-1","summary":"nettle vulnerability","details":"It was discovered that Nettle incorrectly handled signature verification.\nA remote attacker could use this issue to cause Nettle to crash, resulting\nin a denial of service, or possibly force invalid signatures.\n","modified":"2026-02-10T04:42:08Z","published":"2021-04-13T15:00:11Z","related":["UBUNTU-CVE-2021-20305"],"upstream":["CVE-2021-20305","UBUNTU-CVE-2021-20305"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4906-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-20305"}],"affected":[{"package":{"name":"nettle","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/nettle@3.2-1ubuntu0.16.04.2?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.2-1ubuntu0.16.04.2"}]}],"versions":["3.1.1-4","3.2-1","3.2-1ubuntu0.16.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"3.2-1ubuntu0.16.04.2","binary_name":"libhogweed4"},{"binary_version":"3.2-1ubuntu0.16.04.2","binary_name":"libnettle6"},{"binary_version":"3.2-1ubuntu0.16.04.2","binary_name":"nettle-bin"},{"binary_version":"3.2-1ubuntu0.16.04.2","binary_name":"nettle-dev"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4906-1.json","cves_map":{"ecosystem":"Ubuntu:16.04:LTS","cves":[{"id":"CVE-2021-20305","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]}}},{"package":{"name":"nettle","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/nettle@3.4-1ubuntu0.1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4-1ubuntu0.1"}]}],"versions":["3.3-2","3.4-1"],"ecosystem_specific":{"binaries":[{"binary_version":"3.4-1ubuntu0.1","binary_name":"libhogweed4"},{"binary_version":"3.4-1ubuntu0.1","binary_name":"libnettle6"},{"binary_version":"3.4-1ubuntu0.1","binary_name":"nettle-bin"},{"binary_version":"3.4-1ubuntu0.1","binary_name":"nettle-dev"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4906-1.json","cves_map":{"ecosystem":"Ubuntu:18.04:LTS","cves":[{"id":"CVE-2021-20305","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]}}},{"package":{"name":"nettle","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/nettle@3.5.1+really3.5.1-2ubuntu0.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.5.1+really3.5.1-2ubuntu0.1"}]}],"versions":["3.4.1-1","3.5.1+really3.5.1-2"],"ecosystem_specific":{"binaries":[{"binary_version":"3.5.1+really3.5.1-2ubuntu0.1","binary_name":"libhogweed5"},{"binary_version":"3.5.1+really3.5.1-2ubuntu0.1","binary_name":"libnettle7"},{"binary_version":"3.5.1+really3.5.1-2ubuntu0.1","binary_name":"nettle-bin"},{"binary_version":"3.5.1+really3.5.1-2ubuntu0.1","binary_name":"nettle-dev"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4906-1.json","cves_map":{"ecosystem":"Ubuntu:20.04:LTS","cves":[{"id":"CVE-2021-20305","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]}}}],"schema_version":"1.7.3"}