CVE-2026-55620
Description
A flaw was found in eml_parser, a Python module designed for parsing email files. A remote attacker can exploit a vulnerability in how the module processes Received: headers containing deeply nested parentheses. By submitting specially crafted email files, an attacker can cause excessive CPU usage, leading to significant processing delays, system slowdowns, and potential service outages. This can impact synchronous gateways, sandboxes, and real-time email triage systems.
Statement
Red Hat Product Security has determined that this vulnerability does not affect any currently supported Red Hat product. This assessment may evolve based on further analysis and discovery. For more information about this vulnerability and the products it affects, please see the linked references.
Mitigation
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.
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU)
Attackers can create crafted inputs that intentionally cause the regular expression to use excessive backtracking in a way that causes the CPU consumption to spike.
Frequently Asked Questions
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