CVE-2021-22890
- State
- Published
- Severity
- 4.3 Medium
- Published
- Apr 1, 2021
- Updated
- Oct 14, 2026
- Reserved
- Jan 6, 2021
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.3 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N | CISA-ADP |
Weaknesses
- CWE-300 Man-in-the-Middle (CWE-300)
Affected Products
| Product | Versions |
|---|---|
https://github.com/curl/curln/a |
|
References
- https://hackerone.com/reports/1129529
- https://curl.se/docs/CVE-2021-22890.html
- FEDORA-2021-cab5c9befbvendor-advisory
- FEDORA-2021-065371f385vendor-advisory
- FEDORA-2021-26a293c72bvendor-advisory
- GLSA-202105-36vendor-advisory
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://security.netapp.com/advisory/ntap-20210521-0007/
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://cert-portal.siemens.com/productcert/html/ssa-389290.html
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
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