CVE-2021-22890
Published: 31 March 2021
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.
Medium
CVSS 3 base score: 3.7
Status
| Package | Release | Status |
|---|---|---|
|
curl Launchpad, Ubuntu, Debian |
Upstream |
Needs triage
|
| Ubuntu 20.10 (Groovy Gorilla) |
Released
(7.68.0-1ubuntu4.3)
|
|
| Ubuntu 20.04 LTS (Focal Fossa) |
Released
(7.68.0-1ubuntu2.5)
|
|
| Ubuntu 18.04 LTS (Bionic Beaver) |
Not vulnerable
(code not present)
|
|
| Ubuntu 16.04 ESM (Xenial Xerus) |
Not vulnerable
(code not present)
|
|
| Ubuntu 14.04 ESM (Trusty Tahr) |
Not vulnerable
(code not present)
|
|
|
Patches: Vendor: https://curl.se/EQo2A9nBnMI68.patch |
||