CVE-2022-1713 (published 2022-05-16T15:15Z)

SSRF on /proxy in GitHub repository jgraph/drawio prior to 18.0.4. An attacker can make a request as the server and read its contents. This can lead to a leak of sensitive information.

Severity: MEDIUM
CVSS v2 base score: 5.0 (AV:N/AC:L/Au:N/C:P/I:N/A:N)
CVSS v3 base score: 7.5, HIGH (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

Weakness information:
cwe_id: CWE-918
cwe_name: Server-Side Request Forgery (SSRF)
description: The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
extended_description: By providing URLs to unexpected hosts or ports, attackers can make it appear that the server is sending the request, possibly bypassing access controls such as firewalls that prevent the attackers from accessing the URLs directly. The server can be used as a proxy to conduct port scanning of hosts in internal networks, use other URLs such as that can access documents on the system (using file://), or use other protocols such as gopher:// or tftp://, which may provide greater control over the contents of requests.
         

Fix information:
repo_url: https://github.com/jgraph/drawio
commit_details: repo_url: https://github.com/jgraph/drawio
author: David Benson
author_date: 2022-05-13 17:39:58+01:00
msg: 18.0.3 release
repository: repo_url: https://github.com/jgraph/drawio
repo_name: jgraph/drawio
description: draw.io is a JavaScript, client-side editor for general diagramming.
repo_language: JavaScript
owner: jgraph
file_changes: filename: ProxyServlet.java
change_type: ModificationType.MODIFY
diff: @@ -15,6 +15,7 @@ import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLConnection;
 import java.net.UnknownHostException;
+import java.net.InetAddress;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -245,42 +246,51 @@ public class ProxyServlet extends HttpServlet
 			{
 				URL parsedUrl = new URL(url);
 				String protocol = parsedUrl.getProtocol();
-				String host = parsedUrl.getHost().toLowerCase();
+				String host = parsedUrl.getHost();
+				InetAddress address = InetAddress.getByName(host);
+				String hostAddress = address.getHostAddress();
+				host = host.toLowerCase();
 
 				return (protocol.equals("http") || protocol.equals("https"))
-						&& !host.endsWith(".internal")
-						&& !host.endsWith(".local")
-						&& !host.contains("localhost")
-						&& !host.startsWith("0.") // 0.0.0.0/8
-						&& !host.startsWith("10.") // 10.0.0.0/8
-						&& !host.startsWith("127.") // 127.0.0.0/8
-						&& !host.startsWith("169.254.") // 169.254.0.0/16
-						&& !host.startsWith("172.16.") // 172.16.0.0/12
-						&& !host.startsWith("172.17.") // 172.16.0.0/12
-						&& !host.startsWith("172.18.") // 172.16.0.0/12
-						&& !host.startsWith("172.19.") // 172.16.0.0/12
-						&& !host.startsWith("172.20.") // 172.16.0.0/12
-						&& !host.startsWith("172.21.") // 172.16.0.0/12
-						&& !host.startsWith("172.22.") // 172.16.0.0/12
-						&& !host.startsWith("172.23.") // 172.16.0.0/12
-						&& !host.startsWith("172.24.") // 172.16.0.0/12
-						&& !host.startsWith("172.25.") // 172.16.0.0/12
-						&& !host.startsWith("172.26.") // 172.16.0.0/12
-						&& !host.startsWith("172.27.") // 172.16.0.0/12
-						&& !host.startsWith("172.28.") // 172.16.0.0/12
-						&& !host.startsWith("172.29.") // 172.16.0.0/12
-						&& !host.startsWith("172.30.") // 172.16.0.0/12
-						&& !host.startsWith("172.31.") // 172.16.0.0/12
-						&& !host.startsWith("192.0.0.") // 192.0.0.0/24
-						&& !host.startsWith("192.168.") // 192.168.0.0/16
-						&& !host.startsWith("198.18.") // 198.18.0.0/15
-						&& !host.startsWith("198.19.") // 198.18.0.0/15
+						&& !address.isAnyLocalAddress()
+						&& !address.isLoopbackAddress()
+						&& !host.endsWith(".internal") // Redundant
+						&& !host.endsWith(".local") // Redundant
+						&& !host.contains("localhost") // Redundant
+						&& !hostAddress.startsWith("0.") // 0.0.0.0/8 
+						&& !hostAddress.startsWith("10.") // 10.0.0.0/8
+						&& !hostAddress.startsWith("127.") // 127.0.0.0/8
+						&& !hostAddress.startsWith("169.254.") // 169.254.0.0/16
+						&& !hostAddress.startsWith("172.16.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.17.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.18.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.19.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.20.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.21.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.22.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.23.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.24.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.25.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.26.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.27.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.28.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.29.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.30.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("172.31.") // 172.16.0.0/12
+						&& !hostAddress.startsWith("192.0.0.") // 192.0.0.0/24
+						&& !hostAddress.startsWith("192.168.") // 192.168.0.0/16
+						&& !hostAddress.startsWith("198.18.") // 198.18.0.0/15
+						&& !hostAddress.startsWith("198.19.") // 198.18.0.0/15
 						&& !host.endsWith(".arpa"); // reverse domain (needed?)
 			}
 			catch (MalformedURLException e)
 			{
 				return false;
 			}
+			catch (UnknownHostException e)
+			{
+				return false;
+			}
 		}
 		else
 		{

programming_language: Java