CVE-2026-25224
Fastify Vulnerable to DoS via Unbounded Memory Allocation in sendWebStream
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
Fastify is a fast and low overhead web framework, for Node.js. Prior to version 5.7.3, a denial-of-service vulnerability in Fastify’s Web Streams response handling can allow a remote client to exhaust server memory. Applications that return a ReadableStream (or Response with a Web Stream body) via reply.send() are impacted. A slow or non-reading client can trigger unbounded buffering when backpressure is ignored, leading to process crashes or severe degradation. This issue has been patched in version 5.7.3.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Low3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVDNVD · Analyzed | 3.1 | Low3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
- EPSS (exploitation in 30 days)
- 0.55% · top 54% of all CVEs (5 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 3.7.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npmfastifyGHSA-mrq3-vjjr-p77c (opens in a new tab)
References (3)
- https://github.com/fastify/fastify/security/advisories/GHSA-mrq3-vjjr-p77c (opens in a new tab)x_refsource_CONFIRM
- https://github.com/fastify/fastify/commit/eb11156396f6a5fedaceed0140aed2b7f026be37 (opens in a new tab)x_refsource_MISC
- https://hackerone.com/reports/3524779 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-mrq3-vjjr-p77c (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-25224)Record last updated .