CVE-2023-38545

Description

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.

NVD

Severity: CRITICAL
CVE ID: CVE-2023-38545
CVSS Score: 9.8
CVSS Metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Refrence: NVDMITRE

Proof Of Concept

UTsweetyfish

Simple PoC causing overflow

Refrence: GitHub

imfht

😄 CVE-2023-38545堆溢出的POC和分析文章

Refrence: GitHub

fatmo666

Simple PoC causing overflow

Refrence: GitHub

vanigori

Dockerfile containing all the necessary setup files to demo the exploit

Refrence: GitHub

dbrugman

CVE-2023-38545 POC for the curl command line tool

Refrence: GitHub

bcdannyboy

A proof of concept for testing CVE-2023-38545 against local curl

Refrence: GitHub

d0rb

socks5 heap buffer overflow

Refrence: GitHub

Yang-Shun-Yu

Refrence: GitHub