{"id":"UBUNTU-CVE-2021-33197","details":"In Go before 1.15.13 and 1.16.x before 1.16.5, some configurations of ReverseProxy (from net/http/httputil) result in a situation where an attacker is able to drop arbitrary headers.","modified":"2025-10-24T04:50:22Z","published":"2021-08-02T19:15:00Z","upstream":["CVE-2021-33197"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-33197"},{"type":"REPORT","url":"https://github.com/golang/go/issues/46313"},{"type":"REPORT","url":"https://groups.google.com/g/golang-announce/c/RgCMkAEQjSI"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-33197"}],"affected":[{"package":{"name":"golang-1.16","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/golang-1.16@1.16.2-0ubuntu1~18.04.2+esm1?arch=source&distro=esm-apps/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16.2-0ubuntu1~18.04.2","1.16.2-0ubuntu1~18.04.2+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-1.16","binary_version":"1.16.2-0ubuntu1~18.04.2+esm1"},{"binary_name":"golang-1.16-go","binary_version":"1.16.2-0ubuntu1~18.04.2+esm1"},{"binary_name":"golang-1.16-src","binary_version":"1.16.2-0ubuntu1~18.04.2+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33197.json"}},{"package":{"name":"golang-1.8","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/golang-1.8@1.8.3-2ubuntu1.18.04.1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.3-2ubuntu1","1.8.3-2ubuntu1.18.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.8.3-2ubuntu1.18.04.1","binary_name":"golang-1.8"},{"binary_name":"golang-1.8-go","binary_version":"1.8.3-2ubuntu1.18.04.1"},{"binary_name":"golang-1.8-go-shared-dev","binary_version":"1.8.3-2ubuntu1.18.04.1"},{"binary_name":"golang-1.8-src","binary_version":"1.8.3-2ubuntu1.18.04.1"},{"binary_name":"libgolang-1.8-std1","binary_version":"1.8.3-2ubuntu1.18.04.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33197.json"}},{"package":{"name":"golang-1.16","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/golang-1.16@1.16.2-0ubuntu1~20.04.1+esm1?arch=source&distro=esm-apps/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16.2-0ubuntu1~20.04","1.16.2-0ubuntu1~20.04.1","1.16.2-0ubuntu1~20.04.1+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-1.16","binary_version":"1.16.2-0ubuntu1~20.04.1+esm1"},{"binary_name":"golang-1.16-go","binary_version":"1.16.2-0ubuntu1~20.04.1+esm1"},{"binary_name":"golang-1.16-src","binary_version":"1.16.2-0ubuntu1~20.04.1+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33197.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"},{"type":"Ubuntu","score":"medium"}]}