CVE-2026-15308

A flaw was found in Python. Its incremental HTML parser can be exploited by a remote attacker. By sending specially crafted, uncontrolled data with repeated, incomplete markup declarations, the attacker can cause the system to consume excessive central processing unit (CPU) resources. This leads to a denial of service, making the affected system unresponsive.

This Important vulnerability in Python's html.parser.HTMLParser can lead to a denial of service. By supplying specially crafted, malformed HTML with repeated unterminated markup declarations, an attacker can cause excessive CPU consumption, rendering the system unresponsive. Red Hat products utilizing this parser to process untrusted HTML content are susceptible to resource exhaustion.

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.