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.
CVSS Details
- CVSS 3.1 Base Score: 3.7
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade curl | Aug 22, 2024 | Apr 1, 2021 |
| Debian | — | Upgrade curl | Apr 1, 2021 | Apr 1, 2021 |
| Freebsd | — | Upgrade curl | Nov 4, 2022 | Apr 10, 2021 |
| Gentoo Linux | — | Upgrade net-misc/curl. | May 28, 2021 | Apr 1, 2021 |
| Huawei Euleros 2_0_sp9 | — | Upgrade curlUpgrade libcurl | Jul 2, 2021 | Apr 1, 2021 |
| Oracle Solaris | — | Upgrade web/curl to version 7.76.0-11.4.36.0.1.101.0 on Solaris 11.4 | Aug 27, 2021 | Apr 1, 2021 |
| Splunk | — | Upgrade Splunk Enterprise to version 9.0.5Upgrade Splunk Enterprise to version 9.0.6Upgrade Splunk Universal Forwarder to version 9.0.5Upgrade Splunk Enterprise to version 8.2.11Upgrade Splunk Universal Forwarder to version 9.1.1Upgrade Splunk Enterprise to version 8.2.12Upgrade Splunk Enterprise to version 8.1.14Upgrade Splunk Universal Forwarder to version 8.2.11Upgrade Splunk Universal Forwarder to version 8.1.14Upgrade Splunk Universal Forwarder to version 9.0.6Upgrade Splunk Universal Forwarder to version 8.2.12Upgrade Splunk Enterprise to version 9.1.1 | Sep 30, 2025 | Apr 1, 2021 |
| Suse | — | Upgrade libcurl4-miniUpgrade libcurl-mini-develUpgrade libcurl-devel-32bitUpgrade libcurl4-32bitUpgrade curlUpgrade libcurl4Upgrade libcurl-develUpgrade curl-mini | Apr 7, 2021 | Mar 31, 2021 |
| Ubuntu | — | Upgrade curlUpgrade libcurl3-gnutlsUpgrade libcurl3-nssUpgrade libcurl4 | Apr 1, 2021 | Mar 31, 2021 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Jan 20, 2025 | Apr 1, 2021 |
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