SSRF in Geysermc Geyser
CVE-2026-42188
Geyser is a bridge between Minecraft: Bedrock Edition and Minecraft: Java Edition. Prior to 2.9.3, a server-side request forgery (SSRF) vulnerability exists in Geyser’s handling of Bedrock player head texture data. By supplying a crafted Base64-encoded skin texture URL via the /give command, an attacker can cause the Minecraft server to issue arbitrary HTTP GET requests to attacker-controlled or internal endpoints. This occurs server-side, without proper URL validation, and can be triggered by a Bedrock client. This vulnerability is fixed in 2.9.3.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 2.4 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (18.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 18.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Geysermc Geyser — versions < 2.9.3
Weakness classification (CWE)
References
- github.com/GeyserMC/Geyser/security/advisories/GHSA-xcfg-fcr5-gw9r (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-42188?
- CVE-2026-42188 is a low-severity vulnerability in Geysermc Geyser, classified under Server-Side Request Forgery (SSRF). CVSS score: 2.4/10. Published 2026-05-11.
- How severe is CVE-2026-42188?
- Low severity. CVSS v3 base score is 2.4 out of 10.