id: PYSEC-2026-1906
published: "2026-07-07T16:03:09.250252Z"
modified: "2026-07-07T17:25:22.022602Z"
aliases:
- CVE-2025-6176
- GHSA-2qfp-q593-8484
summary: Scrapy is vulnerable to a denial of service (DoS) attack due to flaws in brotli decompression implementation
details: Scrapy versions up to 2.13.3 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. Mitigation for this vulnerability needs security enhancement added in brotli v1.2.0.
affected:
- package:
    name: scrapy
    ecosystem: PyPI
    purl: pkg:pypi/scrapy
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: "0"
    - fixed: 2.13.4
  versions:
  - 0.10.4.2364
  - 0.12.0.2550
  - 0.14.1
  - 0.14.2
  - 0.14.3
  - 0.14.4
  - 0.16.0
  - 0.16.1
  - 0.16.2
  - 0.16.3
  - 0.16.4
  - 0.16.5
  - 0.18.0
  - 0.18.1
  - 0.18.2
  - 0.18.3
  - 0.18.4
  - 0.20.0
  - 0.20.1
  - 0.20.2
  - 0.22.0
  - 0.22.1
  - 0.22.2
  - 0.24.0
  - 0.24.1
  - 0.24.2
  - 0.24.3
  - 0.24.4
  - 0.24.5
  - 0.24.6
  - "0.7"
  - "0.8"
  - "0.9"
  - 1.0.0
  - 1.0.0rc1
  - 1.0.0rc2
  - 1.0.0rc3
  - 1.0.1
  - 1.0.2
  - 1.0.3
  - 1.0.4
  - 1.0.5
  - 1.0.6
  - 1.0.7
  - 1.1.0
  - 1.1.0rc1
  - 1.1.0rc2
  - 1.1.0rc3
  - 1.1.0rc4
  - 1.1.1
  - 1.1.2
  - 1.1.3
  - 1.1.4
  - 1.2.0
  - 1.2.1
  - 1.2.2
  - 1.2.3
  - 1.3.0
  - 1.3.1
  - 1.3.2
  - 1.3.3
  - 1.4.0
  - 1.5.0
  - 1.5.1
  - 1.5.2
  - 1.6.0
  - 1.7.0
  - 1.7.1
  - 1.7.2
  - 1.7.3
  - 1.7.4
  - 1.8.0
  - 1.8.1
  - 1.8.2
  - 1.8.3
  - 1.8.4
  - 2.0.0
  - 2.0.1
  - 2.1.0
  - 2.10.0
  - 2.10.1
  - 2.11.0
  - 2.11.1
  - 2.11.2
  - 2.12.0
  - 2.13.0
  - 2.13.1
  - 2.13.2
  - 2.13.3
  - 2.2.0
  - 2.2.1
  - 2.3.0
  - 2.4.0
  - 2.4.1
  - 2.5.0
  - 2.5.1
  - 2.6.0
  - 2.6.1
  - 2.6.2
  - 2.6.3
  - 2.7.0
  - 2.7.1
  - 2.8.0
  - 2.9.0
references:
- type: ADVISORY
  url: https://nvd.nist.gov/vuln/detail/CVE-2025-6176
- type: WEB
  url: https://github.com/google/brotli/issues/1327
- type: WEB
  url: https://github.com/google/brotli/issues/1375
- type: WEB
  url: https://github.com/google/brotli/pull/1234
- type: WEB
  url: https://github.com/scrapy/scrapy/pull/7134
- type: WEB
  url: https://github.com/google/brotli/commit/67d78bc41db1a0d03f2e763497748f2f69946627
- type: FIX
  url: https://github.com/scrapy/scrapy/commit/14737e91edc513967f516fc839cc9c8a4f8d91da
- type: PACKAGE
  url: https://github.com/google/brotli
- type: WEB
  url: https://github.com/google/brotli/releases/tag/v1.2.0
- type: WEB
  url: https://huntr.com/bounties/2c26a886-5984-47ee-a421-0d5fe1344eb0
- type: PACKAGE
  url: https://pypi.org/project/scrapy
- type: ADVISORY
  url: https://github.com/advisories/GHSA-2qfp-q593-8484
severity:
- type: CVSS_V3
  score: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H