CVE-2026-90927

filebrowser through 2.63.23 fails to limit WebSocket message size in the /api/command handler before checking permissions, allowing authenticated users to buffer arbitrarily large messages. Attackers can send oversized WebSocket messages to exhaust server heap memory and cause denial of service regardless of EnableExec setting or Execute permission.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/filebrowser/filebrowser/security/advisories/GHSA-39cx-23x9-5c8p
https://www.vulncheck.com/advisories/filebrowser-through-2.63.23-denial-of-service-via-unbounded-websocket-message

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-14 13:19

Updated : 2026-09-14 13:19

NVD link : CVE-2026-90927

Mitre link : CVE-2026-90927

CVE.ORG link : CVE-2026-90927

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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