CVE-2026-31889
HMAC Authentication Bypass in Shopware App Registration Enables Hijacking
Publication date: 2026-03-11
Last updated on: 2026-03-16
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| shopware | shopware | to 6.6.10.15 (exc) |
| shopware | shopware | From 6.7.0.0 (inc) to 6.7.8.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-290 | This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
[{'type': 'paragraph', 'content': "CVE-2026-31889 is a high-severity vulnerability in Shopware's app registration and re-registration flow that uses a legacy HMAC-based authentication mechanism."}, {'type': 'paragraph', 'content': 'The flaw allows an attacker who possesses certain app-side secrets to hijack the communication channel between a Shopware shop and an app by abusing the app re-registration process.'}, {'type': 'paragraph', 'content': 'Specifically, the vulnerability arises because the shop installation is not sufficiently bound to its original domain during re-registration, allowing the shop URL to be updated without verifying control over the previously registered shop or domain.'}, {'type': 'paragraph', 'content': 'This enables an attacker to redirect app traffic to a domain they control, intercept and tamper with data, and obtain API credentials intended for the legitimate shop.'}, {'type': 'paragraph', 'content': 'The issue affects all public and private apps using a registrationUrl in their manifest and relying on the legacy registration flow, impacting both on-premise and cloud installations until patched.'}] [1]
How can this vulnerability impact me? :
[{'type': 'paragraph', 'content': 'This vulnerability can allow attackers to hijack the communication channel between your Shopware shop and its apps.'}, {'type': 'paragraph', 'content': 'By abusing the app re-registration process, an attacker can redirect app traffic to an attacker-controlled domain, enabling interception and tampering of data.'}, {'type': 'paragraph', 'content': "Attackers may also obtain API credentials intended for your legitimate shop, potentially leading to unauthorized access and manipulation of your shop's data and operations."}, {'type': 'paragraph', 'content': "This can compromise the integrity, confidentiality, and availability of your shop's app integrations."}] [1]
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by monitoring and analyzing app re-registration events in the Shopware system, especially looking for suspicious changes in the shop-url without proper verification or unexpected re-registrations that could indicate hijacking attempts.
Enhanced logging and monitoring of re-registrations are part of the recommended fixes, so reviewing these logs for anomalies is crucial.
Specific commands are not provided in the available resources, but general approaches include checking Shopware logs for re-registration events and verifying the integrity of app registration URLs.
What immediate steps should I take to mitigate this vulnerability?
- Upgrade Shopware to the fixed versions 6.6.10.15 or 6.7.8.1 or later.
- Install the latest Shopware Security Plugin if upgrading the core is not immediately possible.
- Update all installed apps to their latest versions.
- Re-install or rotate API keys and secrets if there is any suspicion of compromise.
- For app manufacturers and partners, update SDKs and implementations to validate both shopware-app-signature and shopware-shop-signature during app re-registration.
- Review and test apps to ensure proper validation of changed shop URLs and secure handling of secrets.