CVE-2018-10917 in Pulp
Summary
by MITRE
pulp 2.16.x and possibly older is vulnerable to an improper path parsing. A malicious user or a malicious iso feed repository can write to locations accessible to the 'apache' user. This may lead to overwrite of published content on other iso repositories.
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Analysis
by VulDB Data Team • 05/02/2023
The vulnerability identified as CVE-2018-10917 affects pulp versions 2.16.x and potentially older releases, representing a critical path traversal issue that stems from improper handling of file paths during repository operations. This flaw exists within the pulp content management system which is widely used for managing software repositories including iso images and other package formats. The vulnerability specifically manifests when pulp processes iso feed repositories, where the system fails to properly validate and sanitize file paths, allowing for malicious manipulation of the path resolution logic.
The technical exploitation of this vulnerability occurs through manipulation of iso repository feeds where a malicious actor can craft specific paths that bypass normal access controls. When pulp processes these malformed paths, it fails to properly restrict file system access, enabling the system to write files to locations that should be restricted to the apache user account. This improper path parsing creates a scenario where an attacker can potentially overwrite published content in other iso repositories, effectively allowing for arbitrary file system modifications within the pulp server's designated directories. The vulnerability is classified under CWE-22 as improper limitation of a pathname to a restricted directory, which is a well-known weakness in file system access control mechanisms.
The operational impact of this vulnerability is severe as it allows for content tampering and potential service disruption across multiple iso repositories managed by the same pulp instance. An attacker who successfully exploits this vulnerability can not only overwrite existing iso content but may also inject malicious files that could compromise the integrity of the entire repository system. This creates a significant risk for organizations that rely on pulp for distribution of software packages, as the attack could lead to supply chain compromise where legitimate software distributions are replaced with malicious content. The vulnerability affects the principle of least privilege as it allows unauthorized write access to areas that should only be accessible to the apache user account, potentially enabling further escalation attacks.
Organizations should implement immediate mitigations including upgrading to the latest available version of pulp where this vulnerability has been patched, applying proper input validation and sanitization for all repository path operations, and implementing restrictive file system permissions that prevent the apache user from accessing unauthorized directories. The ATT&CK framework categorizes this vulnerability under T1059 Command and Scripting Interpreter and T1078 Valid Accounts as it may enable adversaries to establish persistence through content manipulation and potentially gain elevated privileges through the apache user account. Additional defensive measures should include monitoring for unusual file system write operations, implementing proper network segmentation to limit access to pulp management interfaces, and conducting regular security audits of repository content to detect unauthorized modifications. Organizations should also consider implementing automated patch management processes to ensure timely application of security updates and maintain comprehensive logging of all repository operations for forensic analysis purposes.