feedparser denial of service vulnerability

The primary impact of CVE-2012-2921 is a denial-of-service condition. An attacker can craft a malicious XML feed that, when parsed by an application using Universal Feed Parser, will consume an excessive amount of memory. This can exhaust server resources, making the application unresponsive and potentially impacting other services running on the same system. The attack is relatively simple to execute, requiring only the creation of a specially crafted XML document. The blast radius depends on the application’s architecture and resource limits; a single vulnerable application could impact the entire server if it consumes all available memory. While no widespread exploitation has been publicly reported, the ease of exploitation makes it a potential target for opportunistic attackers.

1. प्रकाशित2018-07-24
2. संशोधित2024-09-20
3. EPSS अद्यतन2026-04-02

The recommended mitigation for CVE-2012-2921 is to upgrade to Universal Feed Parser version 5.1.2 or later, which contains the fix for this vulnerability. If upgrading is not immediately feasible, consider implementing input validation on XML feeds before parsing them. Specifically, sanitize or reject feeds containing excessively long or complex XML ENTITY declarations. Web application firewalls (WAFs) configured to inspect XML payloads could potentially detect and block malicious feeds. Regularly monitor system resource usage (memory consumption) to detect potential DoS attacks. After upgrading, confirm the fix by attempting to parse a known malicious XML feed (if available) and verifying that memory consumption remains within acceptable limits.