CVE-2020-5724

published 2020-03-30

CVE-2020-5724: The Grandstream UCM6200 series before 1.0.20.22 is vulnerable to an SQL injection via the HTTP server's websockify endpoint. A remote unauthenticated attacker…

Priority P2 66 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C H I N A N

EXPLOIT

The Grandstream UCM6200 series before 1.0.20.22 is vulnerable to an SQL injection via the HTTP server's websockify endpoint. A remote unauthenticated attacker can invoke the challenge action with a crafted username and discover user passwords.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
grandstream	ucm6202_firmware	< 1.0.20.22	1.0.20.22
grandstream	ucm6204_firmware	< 1.0.20.22	1.0.20.22
grandstream	ucm6208_firmware	< 1.0.20.22	1.0.20.22

Detection & IOCs extracted from sources · hover to see the quote

url /websockify↗

port 8888↗

• → Monitor WebSocket connections to the /websockify endpoint for SQL injection patterns in the username field of 'challenge' action requests — successful vs. unsuccessful queries return different HTTP status codes, indicating blind boolean-based SQLi enumeration. ↗
• → Alert on unauthenticated requests invoking the 'challenge' action on the UCM6200 websockify endpoint, especially from external/untrusted sources — exploitation requires no authentication. ↗
• → Look for high-frequency repeated WebSocket challenge requests to /websockify from a single source IP, consistent with automated blind SQL injection enumeration of the users table. ↗

• · Passwords are stored in cleartext in the SQLite users table, meaning successful exploitation of the SQL injection directly yields plaintext credentials — no cracking required. ↗
• · The vulnerability affects Grandstream UCM6200 series firmware before 1.0.20.22; devices running older firmware are fully exposed to unauthenticated credential dumping. ↗

CVSS provenance

nvd v3.1 7.5 HIGH CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd v2.0 5.0 MEDIUM AV:N/AC:L/Au:N/C:P/I:N/A:N

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