CVE-2022-43551

Affected: https://github.com/curl/curl

A vulnerability exists in curl <7.87.0 HSTS check that could be bypassed to trick it to keep using HTTP. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP step even when HTTP is provided in the URL. However, the HSTS mechanism could be bypassed if the host name in the given URL first uses IDN characters that get replaced to ASCII counterparts as part of the IDN conversion. Like using the character UTF-8 U+3002 (IDEOGRAPHIC FULL STOP) instead of the common ASCII full stop (U+002E) `.`. Then in a subsequent request, it does not detect the HSTS state and makes a clear text transfer. Because it would store the info IDN encoded but look for it IDN decoded.

USN-5788-1 — curl vulnerabilities

Affected: Ubuntu:18.04:LTS: curl, Ubuntu:20.04:LTS: curl, Ubuntu:22.04:LTS: curl

Hiroki Kurosawa discovered that curl incorrectly handled HSTS support when certain hostnames included IDN characters. A remote attacker could possibly use this issue to cause curl to use unencrypted connections. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 22.10. (CVE-2022-43551)

It was discovered that curl incorrectly handled denials when using HTTP proxies. A remote attacker could use this issue to cause curl to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2022-43552)

Most recent entries from all

CVE-2022-43551

USN-5788-1 — curl vulnerabilities