{"id":"USN-8883-1","summary":"golang-1.18, golang-1.21, golang-1.24 vulnerability","details":"It was discovered that the Go x/net/idna package incorrectly handled\ncertain Punycode-encoded labels that decoded to ASCII-only labels. An\nattacker could possibly use this issue to bypass hostname-based access\ncontrols and escalate privileges.","modified":"2026-10-06T23:42:35.455056715Z","published":"2026-10-06T14:27:27Z","related":["UBUNTU-CVE-2026-39821"],"upstream":["CVE-2026-39821","UBUNTU-CVE-2026-39821"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8883-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-39821"}],"affected":[{"package":{"name":"golang-1.18","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/golang-1.18?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.18.1-1ubuntu1.3"}]}],"versions":["1.18~beta1-0ubuntu1","1.18~beta2-1ubuntu1","1.18~beta2-1ubuntu2","1.18~rc1-1ubuntu1","1.18-1ubuntu1","1.18.1-1ubuntu1","1.18.1-1ubuntu1.1","1.18.1-1ubuntu1.2"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-1.18","binary_version":"1.18.1-1ubuntu1.3"},{"binary_version":"1.18.1-1ubuntu1.3","binary_name":"golang-1.18-go"},{"binary_name":"golang-1.18-src","binary_version":"1.18.1-1ubuntu1.3"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:22.04:LTS","cves":[{"severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N","type":"CVSS_V3"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N"},{"score":"high","type":"Ubuntu"}],"id":"CVE-2026-39821"}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8883-1.json"}},{"package":{"name":"golang-1.21","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/golang-1.21?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.21.1-1~ubuntu22.04.4"}]}],"versions":["1.21.1-1~ubuntu22.04.1","1.21.1-1~ubuntu22.04.2","1.21.1-1~ubuntu22.04.3"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"1.21.1-1~ubuntu22.04.4","binary_name":"golang-1.21"},{"binary_name":"golang-1.21-go","binary_version":"1.21.1-1~ubuntu22.04.4"},{"binary_version":"1.21.1-1~ubuntu22.04.4","binary_name":"golang-1.21-src"}]},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:22.04:LTS","cves":[{"severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N","type":"CVSS_V3"},{"score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N","type":"CVSS_V3"},{"score":"high","type":"Ubuntu"}],"id":"CVE-2026-39821"}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8883-1.json"}},{"package":{"name":"golang-1.24","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/golang-1.24?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.24.13-2~22.04.2"}]}],"versions":["1.24.4-1ubuntu1~22.04.1","1.24.4-1ubuntu1~22.04.2","1.24.13-2~22.04.1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"golang-1.24","binary_version":"1.24.13-2~22.04.2"},{"binary_name":"golang-1.24-go","binary_version":"1.24.13-2~22.04.2"},{"binary_name":"golang-1.24-src","binary_version":"1.24.13-2~22.04.2"}]},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2026-39821","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N"},{"score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N","type":"CVSS_V3"},{"type":"Ubuntu","score":"high"}]}],"ecosystem":"Ubuntu:22.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8883-1.json"}}],"schema_version":"1.9.0"}