CVE-2026-42188
SSRF in Geyser Prior to 2.9.3 via Crafted Skin Texture URL
Publication date: 2026-05-11
Last updated on: 2026-05-11
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| geysermc | geyser | 2.9.3 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-918 | 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. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in Geyser, a bridge between Minecraft: Bedrock Edition and Minecraft: Java Edition, prior to version 2.9.3. It is a server-side request forgery (SSRF) issue that occurs when Geyser handles Bedrock player head texture data. An attacker can supply a crafted Base64-encoded skin texture URL via the /give command, causing the Minecraft server to make arbitrary HTTP GET requests to attacker-controlled or internal endpoints. This happens on the server side without proper URL validation and can be triggered by a Bedrock client.
How can this vulnerability impact me? :
The vulnerability allows an attacker to make the Minecraft server send arbitrary HTTP GET requests to internal or attacker-controlled endpoints. This can potentially be used to access internal resources or services that are not normally exposed, leading to information disclosure or further attacks within the internal network. However, the CVSS score is relatively low (2.4), indicating limited impact, with only low confidentiality impact and no integrity or availability impact.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade Geyser to version 2.9.3 or later, where the server-side request forgery (SSRF) issue has been fixed.