Affected: curl, Siemens RUGGEDCOM APE1808, Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP, Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy handshake.

When curl is asked to pass along the host name to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that host name can be is 255 bytes.

If the host name is detected to be longer, curl switches to local name resolving and instead passes on the resolved address only. Due to this bug, the local variable that means "let the host resolve the name" could get the wrong value during a slow SOCKS5 handshake, and contrary to the intention, copy the too long host name to the target buffer instead of copying just the resolved address there.

The target buffer being a heap based buffer, and the host name coming from the URL that curl has been told to operate with.

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

Jay Satiro discovered that curl incorrectly handled hostnames when using a SOCKS5 proxy. In environments where curl is configured to use a SOCKS5 proxy, a remote attacker could possibly use this issue to execute arbitrary code. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 23.04. (CVE-2023-38545)

It was discovered that curl incorrectly handled cookies when an application duplicated certain handles. A local attacker could possibly create a cookie file and inject arbitrary cookies into subsequent connections. (CVE-2023-38546)