Cybersecurity - Blog - Valentin Vie

Fix your failed uploads in Nextcloud or Immich due to CrowdSec

02 Jun 2026 3 min read Cybersecurity

A failed upload in my self-hosted stack could be due to multiple reasons : Cloudflare, Caddy, CrowdSec or the service configuration. Let's go through each potential issue one-by-one to resolve these failed upload notifications !

Collect Caddy logs securely using Prometheus: restrict admin API access

24 Mar 2026 4 min read Cybersecurity

Caddy exposes a metrics API which also gives admin access. Let's see how to secure Caddy-Prometheus integration taking this into account.

How to whitelist AppSec WAF rules in CrowdSec to avoid false positives?

24 Feb 2026 4 min read Cybersecurity

I realized the fix last described in part #1 might not work with the Application Security Component (AppSec Component). The previous blog post only worked with the classic remediation component. Let's figure out why !

How to run Trivy scans on your selfhosted Forgejo code repositories?

11 Feb 2026 10 min read Cybersecurity

I have wanted for a long time to integrate container scanning and SAST into my CI/CD pipeline. Let's use Trivy to increase the security of my CICD !

How to deepfake your CEO?

17 Nov 2025 4 min read Cybersecurity

Let's try to create a deepfake of Barack Obama to illustrate how easy it is for an attacker to impersonate your CEO and launch social engineering attacks.