CVE-2026-39376
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
07/04/2026
Last modified:
08/04/2026
Description
FastFeedParser is a high performance RSS, Atom and RDF parser. Prior to 0.5.10, when parse() fetches a URL that returns an HTML page containing a tag, it recursively calls itself with the redirect URL — with no depth limit, no visited-URL deduplication, and no redirect count cap. An attacker-controlled server that returns an infinite chain of HTML meta-refresh responses causes unbounded recursion, exhausting the Python call stack and crashing the process. This vulnerability can also be chained with the companion SSRF issue to reach internal network targets after bypassing the initial URL check. This vulnerability is fixed in 0.5.10.
Impact
Base Score 3.x
7.50
Severity 3.x
HIGH