https://db.gcve.eu/rss/recent/all/10 Most recent entries from all 2026-10-10T10:48:20.041406+00:00 Vulnerability-Lookup info@gcve.eu python-feedgen Contains only the most 10 recent entries. https://db.gcve.eu/vuln/fkie_cve-2026-106491 fkie_cve-2026-106491 2026-10-10T10:48:20.072624+00:00

Backstage is an open framework for building developer portals. Prior to 0.6.17, the @backstage/plugin-proxy-backend package is affected by improper input validation in proxy-backend. An authenticated Backstage user could craft a request URL that causes the proxy-backend to forward the request to a path outside the configured base path on the target server. This is limited to target servers already configured as proxy endpoints and requires Backstage authentication by default. This issue is fixed in version 0.6.17.

 https://db.gcve.eu/vuln/ghsa-9ghw-48h5-v2w5 GHSA-9ghw-48h5-v2w5 — Backstage: Improper input validation in proxy-backend 2026-10-10T10:48:20.072704+00:00

Affected: npm: @backstage/plugin-proxy-backend

### Impact

An authenticated Backstage user could craft a request URL that causes the proxy-backend to forward the request to a path outside the configured base path on the target server. This is limited to target servers already configured as proxy endpoints and requires Backstage authentication by default.

### Patches

Patched in `@backstage/plugin-proxy-backend` version `0.6.17`

### Workarounds

- Deploy a reverse proxy or WAF in front of Backstage that normalizes request paths before they reach the backend.