{"id":"UBUNTU-CVE-2018-12556","details":"The signature verification routine in install.sh in yarnpkg/website through 2018-06-05 only verifies that the yarn release is signed by any (arbitrary) key in the local keyring of the user, and does not pin the signature to the yarn release key, which allows remote attackers to sign tampered yarn release packages with their own key.","modified":"2026-05-20T16:03:23.044756857Z","published":"2019-05-16T17:29:00Z","upstream":["CVE-2018-12556"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2018-12556"},{"type":"REPORT","url":"http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.html"},{"type":"REPORT","url":"http://seclists.org/fulldisclosure/2019/Apr/38"},{"type":"REPORT","url":"https://github.com/RUB-NDS/Johnny-You-Are-Fired"},{"type":"REPORT","url":"https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdf"},{"type":"REPORT","url":"https://github.com/yarnpkg/website/commits/master"},{"type":"REPORT","url":"https://www.openwall.com/lists/oss-security/2019/04/30/4"},{"type":"REPORT","url":"https://neopg.io/blog/yarn-signature-bypass/"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2018-12556"}],"affected":[{"package":{"name":"node-yarnpkg","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/node-yarnpkg?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.13.0-1build1","1.13.0-3","1.19.1-1","1.22.4-2"],"ecosystem_specific":{"binaries":[{"binary_name":"yarnpkg","binary_version":"1.22.4-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-12556.json"}},{"package":{"name":"node-yarnpkg","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/node-yarnpkg?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.22.10+~cs22.25.14-3","1.22.10+~cs22.25.14-4","1.22.10+~cs22.25.14-5","1.22.10+~cs22.25.14-8"],"ecosystem_specific":{"binaries":[{"binary_name":"yarnpkg","binary_version":"1.22.10+~cs22.25.14-8"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-12556.json"}},{"package":{"name":"node-yarnpkg","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/node-yarnpkg?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.22.19+~cs24.27.18-2","1.22.19+~cs24.27.18-4"],"ecosystem_specific":{"binaries":[{"binary_name":"yarnpkg","binary_version":"1.22.19+~cs24.27.18-4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-12556.json"}},{"package":{"name":"node-yarnpkg","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/node-yarnpkg?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.0.2+dfsg-3","4.1.0+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"yarnpkg","binary_version":"4.1.0+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-12556.json"}},{"package":{"name":"node-yarnpkg","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/node-yarnpkg?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.0+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"yarnpkg","binary_version":"4.1.0+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-12556.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N"},{"type":"Ubuntu","score":"medium"}]}