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 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.
Fix
Patch, vendor advisory and mitigation references on NVD 6
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf Patch, Third Party Advisory
- https://curl.se/docs/CVE-2021-22890.html Patch, Vendor Advisory
- https://hackerone.com/reports/1129529 Exploit, Issue Tracking, Patch, Third Party Advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf Patch, Third Party Advisory
- https://curl.se/docs/CVE-2021-22890.html Patch, Vendor Advisory
- https://hackerone.com/reports/1129529 Exploit, Issue Tracking, Patch, Third Party Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 3.7 · haxx, fedoraproject, netappNVD modified 2026-10-14 11:16
Affected (CPE criteria) 14
cpe:2.3:a:haxx:libcurl:*:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*cpe:2.3:h:netapp:hci_storage_node:-:*:*:*:*:*:*:*cpe:2.3:o:broadcom:fabric_operating_system:-:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*cpe:2.3:a:siemens:sinec_infrastructure_network_services:*:*:*:*:*:*:*:*cpe:2.3:a:oracle:communications_billing_and_revenue_management:12.0.0.3.0:*:*:*:*:*:*:*cpe:2.3:a:oracle:essbase:21.2:*:*:*:*:*:*:*cpe:2.3:a:splunk:universal_forwarder:*:*:*:*:*:*:*:*cpe:2.3:a:splunk:universal_forwarder:9.1.0:*:*:*:*:*:*:*
References 20
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf Patch, Third Party Advisory
- https://curl.se/docs/CVE-2021-22890.html Patch, Vendor Advisory
- https://hackerone.com/reports/1129529 Exploit, Issue Tracking, Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2ZC5BMIOKLBQJSFCHEDN2G2C2SH274BP/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ITVWPVGLFISU5BJC2BXBRYSDXTXE2YGC/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KQUIOYX2KUU6FIUZVB5WWZ6JHSSYSQWJ/ Mailing List, Third Party Advisory
- https://security.gentoo.org/glsa/202105-36 Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210521-0007/ Third Party Advisory
- https://www.oracle.com//security-alerts/cpujul2021.html Third Party Advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf Patch, Third Party Advisory
- https://curl.se/docs/CVE-2021-22890.html Patch, Vendor Advisory
- https://hackerone.com/reports/1129529 Exploit, Issue Tracking, Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2ZC5BMIOKLBQJSFCHEDN2G2C2SH274BP/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ITVWPVGLFISU5BJC2BXBRYSDXTXE2YGC/ Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KQUIOYX2KUU6FIUZVB5WWZ6JHSSYSQWJ/ Mailing List, Third Party Advisory
- https://security.gentoo.org/glsa/202105-36 Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210521-0007/ Third Party Advisory
- https://www.oracle.com//security-alerts/cpujul2021.html Third Party Advisory
- https://cert-portal.siemens.com/productcert/html/ssa-389290.html
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html