CVE-2024-45802

A flaw was found in Squid. When configured as a reverse proxy with Edge Side Includes (ESI) enabled, improper input validation and resource handling during the processing of ESI response content allow an upstream server to cause a Denial of Service (DoS). By returning specially crafted ESI markup or oversized headers, a malicious server can crash the proxy process or exhaust system resources, disrupting service for all connected clients.

This vulnerability is rated as Important severity because an unauthenticated remote entity can trigger an unhandled failure in the Squid daemon, leading to an immediate denial of service that disrupts caching and proxying operations for all users. In Red Hat Enterprise Linux, Squid packages are built with Edge Side Includes (ESI) support active, which exposes instances configured in reverse-proxy or accelerator topologies to malformed responses from upstream servers. Standard forward proxy deployments that do not inspect or parse ESI elements from backend HTTP servers are not vulnerable to this condition.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.