🎯 New Report #3303283: Unauthenticated blind SSRF in Circles signature verification bypasses Nextcloud local-address protections
🔺Severity: Medium
👽 Reporter: 0x0doteth
⭐️ Reputation: 1507
🛠 State: resolved
💼 Team: Nextcloud
💵 Bounty: null
🕐 Submitted: 2025-08-18
⏰ Disclosed: 2026-09-17 06:22:37
📝 Summary: A blind SSRF vulnerability was discovered in the Circles app for Nextcloud. The vulnerability allowed unauthenticated users to force the server to fetch internal URLs, bypassing local-address protections in Nextcloud. The vulnerability was caused by the Circles app's signature verification process, which fetched an attacker-provided URL before trust was established.
📂 Report JSON File: 3303283
@hackeronereports