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Security: WS-Rollenprüfung, JWT-Cookie statt localStorage, XSS/SSRF-Fixes, RDP-Consent-Secret
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- WebSocket Shell/RDP: Rollenprüfung statt nur JWT-Gültigkeit (war: jeder eingeloggte User konnte fremde Agents per Shell/RDP übernehmen)
- JWT_SECRET: Server bricht ab statt mit unsicherem Default weiterzulaufen
- Auth: Token läuft jetzt über httpOnly-Cookie statt localStorage (XSS-Schutz gegen Session-Diebstahl)
- WS-Auth: Token nicht mehr als URL-Query-Param (landete in nginx-Logs), sondern als erste Message bzw. automatisch via Cookie
- Frontend: toter Rollen-Check (isSuperAdmin/isAdmin ohne Funktionsaufruf) in AgentDetailPage gefixt
- XSS: DOMPurify-Sanitizing für alle marked.parse()-Renderstellen (KI-Antworten, Kommentare, Knowledge Base)
- E-Mail: HTML-Escaping für alle ticket-gesteuerten Felder (auch über öffentliche Ticket-Route erreichbar)
- SSRF-Schutz beim Knowledge-Base-URL-Import (blockt private/Loopback-Adressen)
- TV-Dashboard: Shared-Key statt komplett offenem Endpoint
- Striktes Rate-Limit auf /login, must_change_password serverseitig erzwungen
- Agent (C#) v2.7.0: RDP-Consent/Disconnect/Capture verlangen jetzt ein Pro-Session-Secret (war: jeder lokale Prozess konnte Consent vortäuschen), DataDir-ACL für agent.log/status.json
- FIDO-PINs AES-256-GCM-verschlüsselt statt Klartext, Retention-Job für alte patch_commands/audit_log

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
Simon Grüssing
2026-06-26 13:27:17 +02:00
parent 3ea28def4c
commit 81b1c326fc
47 changed files with 706 additions and 235 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
agent-cs/Services/RtcService.cs
View File

@@ -2,6 +2,7 @@ using System.Diagnostics;
using System.Net;
using System.Net.Sockets;
using System.Net.WebSockets;
using System.Security.Cryptography;
using System.Text;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
@@ -112,15 +113,36 @@ public class RtcService
}
}
private static string GenerateSecret() => Convert.ToHexString(RandomNumberGenerator.GetBytes(16));
// Liest exakt secret.Length Bytes und vergleicht zeitkonstant — verhindert, dass ein beliebiger
// lokaler Prozess sich als der gespawnte Helper ausgibt und Consent/Disconnect/Frames vortäuscht.
private static async Task<bool> ValidateSecretAsync(NetworkStream stream, string secret, CancellationToken ct)
{
var expected = Encoding.ASCII.GetBytes(secret);
var buf = new byte[expected.Length];
var read = 0;
while (read < buf.Length)
{
int n;
try { n = await stream.ReadAsync(buf.AsMemory(read, buf.Length - read), ct); }
catch { return false; }
if (n == 0) return false;
read += n;
}
return CryptographicOperations.FixedTimeEquals(buf, expected);
}
private async Task ConsentAndCaptureAsync(ClientWebSocket ws, int screenIdx, CancellationToken ct)
{
var exePath = System.Diagnostics.Process.GetCurrentProcess().MainModule!.FileName;
var secret = GenerateSecret();
var consentListener = new TcpListener(IPAddress.Loopback, 0);
consentListener.Start();
var consentPort = ((IPEndPoint)consentListener.LocalEndpoint).Port;
if (!SpawnConsentHelper(exePath, consentPort.ToString()))
if (!SpawnConsentHelper(exePath, consentPort.ToString(), secret))
{
consentListener.Stop();
AgentWorker.Log("RDP: Consent-Helper fehlgeschlagen, verweigere Zugriff");
@@ -140,9 +162,15 @@ public class RtcService
{
using var timeoutCts = new CancellationTokenSource(TimeSpan.FromSeconds(35));
using var linked = CancellationTokenSource.CreateLinkedTokenSource(ct, timeoutCts.Token);
using var tcp = await consentListener.AcceptTcpClientAsync(linked.Token);
var b = tcp.GetStream().ReadByte();
accepted = b == 1;
while (!linked.IsCancellationRequested)
{
using var tcp = await consentListener.AcceptTcpClientAsync(linked.Token);
var stream = tcp.GetStream();
if (!await ValidateSecretAsync(stream, secret, linked.Token)) continue; // fremder Connect-Versuch ohne gültiges Secret — ignorieren, weiter warten
var b = stream.ReadByte();
accepted = b == 1;
break;
}
}
catch { accepted = false; }
finally { consentListener.Stop(); }
@@ -174,6 +202,7 @@ public class RtcService
_indicatorListener = new TcpListener(IPAddress.Loopback, 0);
_indicatorListener.Start();
var port = ((IPEndPoint)_indicatorListener.LocalEndpoint).Port;
var secret = GenerateSecret();
_userDisconnectCts = new CancellationTokenSource();
var listener = _indicatorListener;
@@ -182,15 +211,21 @@ public class RtcService
{
try
{
using var tcp = await listener.AcceptTcpClientAsync();
tcp.GetStream().ReadByte();
disconnectCts.Cancel();
AgentWorker.Log("RDP: User hat über Overlay getrennt");
while (true)
{
using var tcp = await listener.AcceptTcpClientAsync();
var stream = tcp.GetStream();
if (!await ValidateSecretAsync(stream, secret, CancellationToken.None)) continue; // fremder Connect-Versuch ohne gültiges Secret
stream.ReadByte();
disconnectCts.Cancel();
AgentWorker.Log("RDP: User hat über Overlay getrennt");
break;
}
}
catch { }
});
_indicatorPid = SessionSpawner.SpawnInUserSession(exePath, $"--rdp-indicator {port}");
_indicatorPid = SessionSpawner.SpawnInUserSession(exePath, $"--rdp-indicator {port} {secret}");
}
catch (Exception ex)
{
@@ -198,22 +233,23 @@ public class RtcService
}
}
private static bool SpawnConsentHelper(string exePath, string portStr)
private static bool SpawnConsentHelper(string exePath, string portStr, string secret)
{
var pid = SessionSpawner.SpawnInUserSession(exePath, $"--rdp-consent {portStr}");
var pid = SessionSpawner.SpawnInUserSession(exePath, $"--rdp-consent {portStr} {secret}");
return pid > 0;
}
private async Task CapturePipeLoopAsync(ClientWebSocket ws, int screenIdx, CancellationToken ct)
{
var exePath = System.Diagnostics.Process.GetCurrentProcess().MainModule!.FileName;
var secret = GenerateSecret();
// TCP Loopback: kein ACL-Problem zwischen SYSTEM-Service und User-Prozess
var listener = new TcpListener(IPAddress.Loopback, 0);
listener.Start();
var port = ((IPEndPoint)listener.LocalEndpoint).Port;
if (!SpawnCaptureHelper(exePath, port.ToString(), screenIdx))
if (!SpawnCaptureHelper(exePath, port.ToString(), screenIdx, secret))
{
listener.Stop();
AgentWorker.Log("RDP: Helper-Start fehlgeschlagen");
@@ -225,7 +261,16 @@ public class RtcService
{
using var connectCts = new CancellationTokenSource(TimeSpan.FromSeconds(15));
using var linked = CancellationTokenSource.CreateLinkedTokenSource(ct, connectCts.Token);
tcp = await listener.AcceptTcpClientAsync(linked.Token);
while (true)
{
var candidate = await listener.AcceptTcpClientAsync(linked.Token);
if (await ValidateSecretAsync(candidate.GetStream(), secret, linked.Token))
{
tcp = candidate;
break;
}
candidate.Dispose(); // fremder Connect-Versuch ohne gültiges Secret — verwerfen, weiter warten
}
}
catch
{
@@ -283,9 +328,9 @@ public class RtcService
AgentWorker.Log("RDP: Frame-Loop beendet");
}
private static bool SpawnCaptureHelper(string exePath, string portStr, int screenIdx = 0)
private static bool SpawnCaptureHelper(string exePath, string portStr, int screenIdx, string secret)
{
var pid = SessionSpawner.SpawnInUserSession(exePath, $"--rdp-capture {portStr} {screenIdx}");
var pid = SessionSpawner.SpawnInUserSession(exePath, $"--rdp-capture {portStr} {screenIdx} {secret}");
return pid > 0;
}
}