CVE-2021-44790 - Guidance for Apache HTTP Server 2.4 vulnerabilities (11/06/2023)

[dpuigdomenec]

Advisory:

Guidance for Apache HTTP Server 2.4 vulnerabilities (11/06/2023)

CVE-2021-44790

Affected version: Out-of-bounds Read vulnerability in mod_macro of Apache HTTP Server. This issue affects Apache HTTP Server: through 2.4.57.

Update 2.4.58 released	2023-10-19
Affects	<=2.4.57

Diagnosis

Execute below command to check the version of Apache HTTP Server 2.4:

sudo apt list --installed | grep apache

If the output showing version less than 2.4.58, you will need to perform the steps to upgrade the apache2 libraries.

Solution

Prerequisites: Your Expedition VM should have connectivity to http://ppa.launchpad.net and subdomains. ONLY required to do the libraries upgrade.

In Expedition CLI execute below commands:

1. Update the package repository:
   sudo apt-add-repository ppa:ondrej/apache2
2. Install deb lib packages:
   sudo apt-get install apache2
3. Check packages are installed
   sudo apt list --installed | grep apache
   Expected output:
   

   apache2-bin/focal,now 2.4.58-1+ubuntu20.04.1+deb.sury.org+1 amd64 [installed,automatic]
   apache2-data/focal,now 2.4.58-1+ubuntu20.04.1+deb.sury.org+1 all [installed,automatic]
   apache2-utils/focal,now 2.4.58-1+ubuntu20.04.1+deb.sury.org+1 amd64 [installed,automatic]
   apache2/focal,now 2.4.58-1+ubuntu20.04.1+deb.sury.org+1 amd64 [installed]
   libapache2-mod-php7.0/now 7.0.33-57+ubuntu20.04.1+deb.sury.org+1 amd64 [installed,upgradable to: 7.0.33-68+ubuntu20.04.1+deb.sury.org+2]​

4. Make /tmp folder writable for apache2 service

• Open file to edit: sudo vi /lib/systemd/system/apache2.service
• Change setting PrivateTmp from true to false (PrivateTmp=false)
• Save file and restart below services: sudo systemctl daemon-reload; sudo systemctl restart apache2