Undici
CVE-2022-35949
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V4 - API and Web Service URL allowlisting, SSRF prevention
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Credential Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | A remote attacker could make the server perform requests to unintended internal or external resources by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAI
undici is an HTTP/1.1 client, written from scratch for Node.js.undici is vulnerable to SSRF (Server-side Request Forgery) when an application takes in user input into the path/pathname option. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Validate and allowlist destination URLs, block requests to internal networks, use network segmentation.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Server-Side Request Forgery (SSRF) (CWE-918), which allows attackers to make the server perform requests to unintended internal or external resources. undici is an HTTP/1.1 client, written from scratch for Node.js.undici is vulnerable to SSRF (Server-side Request Forgery) when an application takes in user input into the path/pathname option of undici.request. If a user specifies a URL such as http://127.0.0.1 or //127.0.0.1 `js const undici = require("undici") undici.request({origin: "http://example.com", pathname: "//127.0.0.1"}) ` Instead of processing the request as http://example.org//127.0.0.1 (or http://example.org/http://127.0.0.1 when http://127.0.0.1 is used), it actually processes the request as http://127.0.0.1/ and sends it to http://127.0.0.1. If a developer passes in user input into path parameter of undici.request, it can result in an _SSRF_ as they will assume that the hostname cannot change, when in actual fact it can change because the specified path parameter is combined with the base URL. This issue was fixed in undici@5.8.1. The best workaround is to validate user input before passing it to the undici.request call. Affected products include: Nodejs Undici.
Know when Undici gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
undici is an HTTP/1.1 client, written from scratch for Node.js.undici is vulnerable to SSRF (Server-side Request Forgery) when an application takes in user input into the path/pathname option of undici.request. If a user specifies a URL such as http://127.0.0.1 or //127.0.0.1 `js const undici = require("undici") undici.request({origin: "http://example.com", pathname: "//127.0.0.1"}) ` Instead of processing the request as http://example.org//127.0.0.1 (or http://example.org/http://127.0.0.1 when http://127.0.0.1 is used), it actually processes the request as http://127.0.0.1/ and sends it to http://127.0.0.1. If a developer passes in user input into path parameter of undici.request, it can result in an _SSRF_ as they will assume that the hostname cannot change, when in actual fact it can change because the specified path parameter is combined with the base URL. This issue was fixed in undici@5.8.1. The best workaround is to validate user input before passing it to the undici.request call.
Blast Radius
ecosystem impact- 8 npm packages depend on undici (7 direct, 1 indirect)
Ecosystem-wide dependent count for version 5.8.2.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Server-Side Request Forgery exploits applications that fetch remote resources based on user-supplied URLs.
Affected Products (CPE)NVD
Memory exhaustion denial of service in the undici WebSocket client (versions 6.17.0 and later) allows a malicious or com
Cross-user information disclosure in undici's cache interceptor allows authenticated users' responses to be served from
Cookie attribute injection in undici's setCookie function allows attacker-controlled domain values or unparsed array ent
Authorization headers are cleared on cross-origin redirect. Rated medium severity (CVSS 6.5), this vulnerability is remo
`Undici.ProxyAgent` never verifies the remote server's certificate, and always exposes all request & response data to th
CRLF injection in undici's HTTP/1.1 dispatcher enables HTTP header injection and potential request smuggling when applic
Undici is an HTTP/1.1 client for Node.js. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable,
undici is an HTTP/1.1 client, written from scratch for Node.js.`=< undici@5.8.0` users are vulnerable to _CRLF Injection
Cross-user information disclosure and a parse-time denial of service in undici's HTTP cache interceptor affect versions
Certificate pinning and custom TLS identity checks can be silently bypassed in undici versions 4.0.0 through 6.29.0, 7.0
Persistent cache poisoning and disclosure of user-specific responses affect undici 7.0.0 through 7.30.0 and 8.0.0 throug
TLS certificate validation bypass in undici's BalancedPool dispatcher silently discards function-valued options - includ
Exploit-DB