Fonttools: Scrapy is vulnerable to a denial of service (DoS) attack due to flaws in brotli decompression
Affects fonttoolsSource GCVE Database
Not known to be exploited · CVSS 7.5 High : upgrade to 4.60.1_2 or 4.45.0 soon.
Data as of 26 Oct 2026, 17:57 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 45% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.60.1_2, 4.45.0
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 31 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade fonttools to 4.60.1_2 or 4.45.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewfonttoolspkg:brew/fonttoolsOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Apply the official patches by upgrading fonttools to version 4.45.0 or later (including 4.60.1_2). These versions include the necessary security enhancements from brotli v1.2.0 to mitigate the decompression bomb attack vector. No additional mitigation is required if patched.
Description
Scrapy versions up to 2.13.3 contain a denial of service (DoS) vulnerability due to improper handling of brotli decompression. The existing protection against decompression bombs does not cover the brotli compression variant, allowing crafted data to cause excessive memory consumption and crash clients with less than 80GB of memory. This flaw is mitigated by security enhancements introduced in brotli version 1.2.0 and fixed in fonttools versions 4.45.0 and 4.60.1_2.
References
- nvd.nist.gov/vuln/detail/CVE-2025-6176 (opens in a new tab)
- github.com/google/brotli/issues/1327 (opens in a new tab)
- github.com/google/brotli/issues/1375 (opens in a new tab)
- github.com/google/brotli/pull/1234 (opens in a new tab)
- github.com/scrapy/scrapy/pull/7134 (opens in a new tab)
- github.com/google/brotli/commit/67d78bc41db1a0d03f2e763497748f2f69946627 (opens in a new tab)
- github.com/scrapy/scrapy/commit/14737e91edc513967f516fc839cc9c8a4f8d91da (opens in a new tab)
- github.com/google/brotli (opens in a new tab)
- github.com/google/brotli/releases/tag/v1.2.0 (opens in a new tab)
- huntr.com/bounties/2c26a886-5984-47ee-a421-0d5fe1344eb0 (opens in a new tab)