9

CVE-2026-33805

Exploit

@fastify/reply-from vulnerable to connection header abuse enabling stripping of proxy-added headers

@fastify/reply-from v12.6.1 and earlier and @fastify/http-proxy v11.4.3 and earlier process the client's Connection header after the proxy has added its own headers via rewriteRequestHeaders. This allows attackers to retroactively strip proxy-added headers from upstream requests by listing them in the Connection header value. Any header added by the proxy for routing, access control, or security purposes can be selectively removed by a client. @fastify/http-proxy is also affected as it delegates to @fastify/reply-from. 

Upgrade to @fastify/reply-from v12.6.2 or @fastify/http-proxy v11.4.4 or later.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Fastify ≫ Reply-from SwPlatformnode.js Version < 12.6.2
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.44% 0.352
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
NIST 8.6 3.9 4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
ce714d77-add3-4f53-aff5-83d477b104bb 9 0 0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
0b0ca135-0b70-47e7-9f44-1890c2a1c46c 7.4 2.2 5.2
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

CWE-644 Improper Neutralization of HTTP Headers for Scripting Syntax

The product does not neutralize or incorrectly neutralizes web scripting syntax in HTTP headers that can be used by web browser components that can process raw headers, such as Flash.

https://cna.openjsf.org/security-advisories.html
Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2458651
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33805.json
https://access.redhat.com/errata/RHSA-2026:10175
https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-gwhp-pf74-vj37
Vendor Advisory
Exploit
Mitigation
https://access.redhat.com/security/cve/CVE-2026-33805