{"id":"CVE-2021-22890","title":"curl 7.63.0 to and including 7.75.0 includes vulnerability that allows a malicious HTTPS proxy to MITM a connection due to bad handling of TLS 1.3 session tickets","summary":"curl 7.63.0 to and including 7.75.0 includes vulnerability that allows a malicious HTTPS proxy to MITM a connection due to bad handling of TLS 1.3 session tickets. When using a HTTPS proxy and TLS 1.3, libcurl can confuse session tickets…","severity":"low","cvss":3.7,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","cwe":["CWE-300","CWE-290"],"vendor":"haxx","product":"libcurl","affected":["libcurl >= 7.63.0, <= 7.75.0","fedora = 32","fedora = 33","fedora = 34","hci_management_node","solidfire","hci_storage_node","fabric_operating_system","debian_linux = 9.0","sinec_infrastructure_network_services < 1.0.1.1","communications_billing_and_revenue_management = 12.0.0.3.0","essbase = 21.2","universal_forwarder >= 8.2.0, < 8.2.12","universal_forwarder >= 9.0.0, < 9.0.6","universal_forwarder = 9.1.0"],"patched":["sinec_infrastructure_network_services 1.0.1.1","universal_forwarder 9.0.6"],"published":"2021-04-01","updated":"2026-10-14","sourceUpdated":"2026-10-14T11:16:52.373","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-22890","references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","label":"support@hackerone.com"},{"url":"https://curl.se/docs/CVE-2021-22890.html","label":"support@hackerone.com"},{"url":"https://hackerone.com/reports/1129529","label":"support@hackerone.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2ZC5BMIOKLBQJSFCHEDN2G2C2SH274BP/","label":"support@hackerone.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ITVWPVGLFISU5BJC2BXBRYSDXTXE2YGC/","label":"support@hackerone.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KQUIOYX2KUU6FIUZVB5WWZ6JHSSYSQWJ/","label":"support@hackerone.com"},{"url":"https://security.gentoo.org/glsa/202105-36","label":"support@hackerone.com"},{"url":"https://security.netapp.com/advisory/ntap-20210521-0007/","label":"support@hackerone.com"},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","label":"support@hackerone.com"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://curl.se/docs/CVE-2021-22890.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://hackerone.com/reports/1129529","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2ZC5BMIOKLBQJSFCHEDN2G2C2SH274BP/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ITVWPVGLFISU5BJC2BXBRYSDXTXE2YGC/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KQUIOYX2KUU6FIUZVB5WWZ6JHSSYSQWJ/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202105-36","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210521-0007/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-389290.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.02978,"epssPercentile":0.86938,"ingestedAt":"2026-10-14T11:27:22.122Z","slug":"CVE-2021-22890","body":"## Overview\n\ncurl 7.63.0 to and including 7.75.0 includes vulnerability that allows a malicious HTTPS proxy to MITM a connection due to bad handling of TLS 1.3 session tickets. When using a HTTPS proxy and TLS 1.3, libcurl can confuse session tickets arriving from the HTTPS proxy but work as if they arrived from the remote server and then wrongly \"short-cut\" the host handshake. When confusing the tickets, a HTTPS proxy can trick libcurl to use the wrong session ticket resume for the host and thereby circumvent the server TLS certificate check and make a MITM attack to be possible to perform unnoticed. Note that such a malicious HTTPS proxy needs to provide a certificate that curl will accept for the MITMed server for an attack to work - unless curl has been told to ignore the server certificate check.\n\n## Affected\n\n- `libcurl >= 7.63.0, <= 7.75.0`\n- `fedora = 32`\n- `fedora = 33`\n- `fedora = 34`\n- `hci_management_node`\n- `solidfire`\n- `hci_storage_node`\n- `fabric_operating_system`\n- `debian_linux = 9.0`\n- `sinec_infrastructure_network_services < 1.0.1.1`\n- `communications_billing_and_revenue_management = 12.0.0.3.0`\n- `essbase = 21.2`\n- `universal_forwarder >= 8.2.0, < 8.2.12`\n- `universal_forwarder >= 9.0.0, < 9.0.6`\n- `universal_forwarder = 9.1.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `sinec_infrastructure_network_services 1.0.1.1`\n- `universal_forwarder 9.0.6`","depth":"sunlit","depthScore":21,"depthScoreParts":{"impact":20.4,"likelihood":0.6,"exploitation":0,"ransomware":0},"changes":[]}