Dirty Pipe Linux Vulnerability: Overwriting Files in Container Images
CVE-2022-0847, known as "Dirty Pipe," is a Linux kernel vulnerability that allows users to overwrite files they can read but should not be able to write to. This vulnerability is particularly concerning for containerized environments using Docker, as it enables the modification of files within container images from inside a container. This can lead to potential attacks where shared images are poisoned, affecting all containers running against that image. The exploit can also override read-only mounted volumes. Systems running Linux kernel 5.8 or above should be patched immediately to mitigate this issue. The vulnerability highlights the importance of regular updates and reboots to ensure patches are effective.
The "Dirty Pipe" vulnerability (CVE-2022-0847) allows attackers to overwrite files within container images from inside a container, posing a significant threat to containerized environments. The attack begins with the adversary gaining access to a container, potentially through valid cloud accounts. Once inside, the attacker exploits the Dirty Pipe vulnerability to escalate privileges and modify files that should be read-only, such as configuration files shared across multiple containers. This is where BlueRock's Read-Only File Protection mechanism comes into play. By enforcing strict read-only policies on critical files and directories, BlueRock effectively prevents unauthorized modifications, ensuring that even if an attacker gains access to a container, they cannot alter the underlying image files. This protection is crucial in maintaining the integrity of containerized applications and preventing the spread of malicious changes across multiple containers.
- T1078.004: Valid Accounts: Cloud Accounts: The article describes how attackers can use the Dirty Pipe vulnerability (CVE-2022-0847) to overwrite files in container images from within a container. This implies that attackers can gain control of a container to execute this exploit. The first step in this attack scenario is the adversary gaining initial access to the container.
- T1068: Exploitation for Privilege Escalation: Once the attacker has access to the container, they utilize the Dirty Pipe vulnerability to modify files that should be read-only. This action is directly manipulating and altering the system's files to achieve their goal, which falls under the category of exploiting a privilege escalation vulnerability.
- T1105: Ingress Tool Transfer: The article mentions that the attacker can modify files from the underlying image, affecting all containers using that shared image. This action of modifying files in a way that affects multiple containers aligns with the technique of Ingress Tool Transfer, where the attacker transfers tools or files into the container to facilitate the attack.
- T1592.003: Gather Victim Host Information: Firmware: The attack's ability to modify configuration files such as nginx.conf to affect multiple running containers demonstrates the attacker’s ability to modify system configurations to maintain persistence or further their goals. This aligns with the concept of modifying system configurations.
- T1070.006: Indicator Removal: Timestomp: Finally, the article advises patching the Linux kernel to mitigate the vulnerability. This suggests that the persistence of the vulnerability can be mitigated by updating the system, highlighting the importance of applying security patches.
