CVE-2021-29136 Explained : Impact and Mitigation

Open Container Initiative umoci before 0.4.7 allows attackers to overwrite arbitrary host paths via a crafted image that causes symlink traversal when "umoci unpack" or "umoci raw unpack" is used.

Understanding CVE-2021-29136

This CVE relates to a vulnerability in Open Container Initiative umoci before version 0.4.7 that can be exploited by attackers to overwrite arbitrary host paths.

What is CVE-2021-29136?

CVE-2021-29136 is a security flaw in umoci, allowing cybercriminals to manipulate host paths through a specially designed image, resulting in symlink traversal during specific operations.

The Impact of CVE-2021-29136

If exploited, this vulnerability could lead to unauthorized data access and potentially enable malicious actors to compromise the integrity of the system by tampering with critical host paths.

Technical Details of CVE-2021-29136

The technical specifics of the CVE include:

Vulnerability Description

The vulnerability in umoci version 0.4.7 allows unauthorized modification of host paths through symlink traversal during "umoci unpack" or "umoci raw unpack" operations.

Affected Systems and Versions

All versions of umoci before 0.4.7 are affected by this vulnerability, putting systems using these versions at risk of exploitation.

Exploitation Mechanism

Cyber attackers can exploit this vulnerability by utilizing a maliciously crafted image, triggering symlink traversal when specific umoci operations are invoked.

Mitigation and Prevention

To address CVE-2021-29136, the following steps are recommended:

Immediate Steps to Take

Update umoci to version 0.4.7 or newer to mitigate the vulnerability.

Long-Term Security Practices

Ensure regular security updates for all software components to prevent similar exploits in the future.

Patching and Updates

Stay informed about security advisories and promptly apply patches released by Open Container Initiative to safeguard against known vulnerabilities.