CVE-2026-33806— fastify vulnerable to Body Schema Validation Bypass via Leading Space in Content-Type Header
Get alerts for future matching vulnerabilitiesLog in to subscribe
I. Basic Information for CVE-2026-33806
Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗ Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.
Vulnerability Title
fastify vulnerable to Body Schema Validation Bypass via Leading Space in Content-Type Header
Source: NVD (National Vulnerability Database)
Vulnerability Description
Impact: Fastify applications using schema.body.content for per-content-type body validation can have validation bypassed entirely by prepending a space to the Content-Type header. The body is still parsed correctly but schema validation is skipped. This is a regression introduced in fastify >= 5.3.2 by the fix for CVE-2025-32442 Patches: Upgrade to fastify v5.8.5 or later. Workarounds: None. Upgrade to the patched version.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Source: NVD (National Vulnerability Database)
Vulnerability Type
CWE-1287
Source: NVD (National Vulnerability Database)
Vulnerability Title
Fastify 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Fastify是Fastify开源的一个 Web 框架。 Fastify 5.8.5之前版本存在安全漏洞，该漏洞源于使用schema.body.content进行按内容类型主体验证时，通过在Content-Type标头前添加空格可完全绕过验证。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
II. Public POCs for CVE-2026-33806
| # | POC Description | Source Link | Shenlong Link |
|---|
AI-Generated POCPremium
No public POC found.
Login to generate AI POCIII. Intelligence Information for CVE-2026-33806
请登录查看更多情报信息。
Advisory · 1
Same Patch Batch · fastify · 2026-04-15 · 3 CVEs total
| CVE-2026-33807 | 9.1 CRITICAL | @fastify/express vulnerable to middleware path doubling causing authentication bypass in c |
| CVE-2026-33808 | @fastify/express vulnerable to middleware authentication bypass via URL normalization gaps |
IV. Related Vulnerabilities
Same product: fastify
- CVE-2026-3635
Fastify request.protocol and request.host spoofable via X-Fo - CVE-2026-3419
Fastify's Missing End Anchor in "subtypeNameReg" Allows Malf - CVE-2026-25223
Fastify's Content-Type header tab character allows body vali - CVE-2026-25224
Fastify Vulnerable to DoS via Unbounded Memory Allocation in - CVE-2025-32442
Fastify vulnerable to invalid content-type parsing, which co
Same vendor: fastify
- CVE-2026-33807
@fastify/express vulnerable to middleware path doubling caus - CVE-2026-33808
@fastify/express vulnerable to middleware authentication byp - CVE-2026-3635
Fastify request.protocol and request.host spoofable via X-Fo - CVE-2026-3419
Fastify's Missing End Anchor in "subtypeNameReg" Allows Malf - CVE-2026-25223
Fastify's Content-Type header tab character allows body vali
Same weakness: CWE-1287
- CVE-2026-0802
AXIS OS 安全漏洞 - CVE-2019-25596
SpotAuditor 5.2.6 Name Field Denial of Service - CVE-2026-2092
Keycloak-services: keycloak: unauthorized access via imprope - CVE-2026-2454
DoS in Calls plugin via malformed msgpack in websocket reque - CVE-2026-25783
Denial of service via malformed User-Agent header in getBrow
V. Comments for CVE-2026-33806
No comments yet