Authentication Bypass by Spoofing in Shopware - CVE-2026-31889
Published: May 20, 2026
Vulnerability identifier: #VU131908
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2026-31889
CWE-ID: CWE-290
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Shopware
Affected software:
Shopware
Shopware
Detailed vulnerability description
The vulnerability allows a remote attacker to obtain API credentials and tamper with app-shop communication.
The vulnerability exists due to authentication bypass by spoofing in the legacy app registration and re-registration flow when processing app re-registration requests that update the shop-url without proving control of the previously registered shop or domain. A remote attacker can re-register an existing app installation with an attacker-controlled domain to obtain API credentials and tamper with app-shop communication.
Exploitation is limited to apps that use a registrationUrl in their app manifest and rely on the legacy HMAC-based registration flow.
How to mitigate CVE-2026-31889
Install security update from vendor's website.