scrapy · Twisted: Unauthenticated Remote Denial of Service
Affects scrapySource GCVE Database
Mentioned vulnerabilities
CVSS 7.5 High.
Data as of 30 Oct 2026, 05:36 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HWhat to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewscrapypkg:brew/scrapyOther threats | Affected
| Fixed in– |
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AI-suggested
Until a fix is available, consider limiting exposure of the Twisted HTTP/2 server to untrusted clients or implementing external rate limiting on HTTP/2 connections to mitigate rapid stream reset abuse.
Description
An unauthenticated remote denial of service vulnerability exists in the Twisted HTTP/2 server (CVE-2023-44487). A remote client can send a sequence of HTTP/2 frames that cause the server to render requests fully before processing stream resets, allowing CPU exhaustion via rapid stream resets on a single connection. This bypasses the concurrent-stream limit and leads to unbounded request processing. The vulnerability affects Twisted web HTTP/2 server version 26.4.0 and later. There is no impact on confidentiality or integrity, and no code execution is possible.
References
- github.com/twisted/twisted/security/advisories/GHSA-vpp8-g58w-m8mp (opens in a new tab)
- github.com/twisted/twisted/pull/12749 (opens in a new tab)
- github.com/twisted/twisted/commit/498939422b69d5a75c4b8f81fa7926423dac534d (opens in a new tab)
- github.com/twisted/twisted (opens in a new tab)
- github.com/twisted/twisted/releases/tag/twisted-26.10.0rc1 (opens in a new tab)
- nvd.nist.gov/vuln/detail/cve-2023-44487 (opens in a new tab)