CVE-2025-6176
Scrapy: python-scrapy: brotli: Python brotli decompression bomb DoS
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · October 31, 2025
Updated · October 9, 2026
Description
Scrapy are vulnerable to a denial of service (DoS) attack due to a flaw in its brotli decompression implementation. The protection mechanism against decompression bombs fails to mitigate the brotli variant, allowing remote servers to crash clients with less than 80GB of available memory. This occurs because brotli can achieve extremely high compression ratios for zero-filled data, leading to excessive memory consumption during decompression.
Statement
This vulnerability is rated Important for Red Hat products. The flaw in Scrapy's brotli decompression implementation allows remote attackers to trigger a denial of service by sending specially crafted brotli-compressed data. This can lead to excessive memory consumption and system instability.
CVSS score applicability
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
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.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-400 · Uncontrolled Resource Consumption