CVE-2026-44552 (GCVE-0-2026-44552)

Vulnerability from cvelistv5 – Published: 2026-05-15 19:57 – Updated: 2026-05-19 13:06
VLAI
Title
Open WebUI: Redis Cache Keys tool_servers and terminal_servers Missing Instance Prefix Enable Cross-Instance Cache Poisoning
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the tool_servers and terminal_servers keys in utils/tools.py do use a prefix. When two or more Open WebUI instances share a Redis database (a supported and documented deployment pattern, e.g., for multi-region deployments, blue-green setups, or cluster topologies), the unprefixed keys collide. An admin on Instance A writing to tool_servers overwrites the value read by Instance B — causing Instance B's users to receive Instance A's tool server configuration. This vulnerability is fixed in 0.9.0.
Severity
8.7 (High)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-19 03:55 UTC
CWE
  • CWE-668 - Exposure of Resource to Wrong Sphere
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
open-webui open-webui Affected: < 0.9.0
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