Impact
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
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.
Patches
This issue was fixed in undici@5.8.1.
Workarounds
The best workaround is to validate user input before passing it to the undici.request call.
For more information
If you have any questions or comments about this advisory:
References
Haxatron Analyst
Impact
undiciis vulnerable to SSRF (Server-side Request Forgery) when an application takes in user input into thepath/pathnameoption ofundici.request.If a user specifies a URL such as
http://127.0.0.1or//127.0.0.1Instead of processing the request as
http://example.org//127.0.0.1(orhttp://example.org/http://127.0.0.1whenhttp://127.0.0.1 is used), it actually processes the request ashttp://127.0.0.1/and sends it tohttp://127.0.0.1.If a developer passes in user input into
pathparameter ofundici.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.Patches
This issue was fixed in
undici@5.8.1.Workarounds
The best workaround is to validate user input before passing it to the
undici.requestcall.For more information
If you have any questions or comments about this advisory:
References