CVE-2021-22890

2021-04-0117:46:17

CWE-300

hackerone

www.cve.org

5.4 Medium

AI Score

Confidence

High

0.004 Low

EPSS

Percentile

72.2%

JSON

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.

CNA Affected

[
  {
    "product": "https://github.com/curl/curl",
    "vendor": "n/a",
    "versions": [
      {
        "status": "affected",
        "version": "7.63.0 to and including 7.75.0"
      }
    ]
  }
]