Things sandboxed by Firejail share the same host kernel. Therefore, kernel vulnerabilities could allow for privilege escalation.
Firejail itself is a security-hole. It is a massive root SetUID binary which can and has been used for privilege escalation. I avoid it entirely. Unprivileged sandboxes are better, but lack the built-in profiles provided by Firejail.
If I was trying to sandbox malware, I would use sydbox. It is memory safe (unlike Firejail or Bubblewrap), unprivileged (unlike Firejail), secure sandbox by default (unlike Bubblewrap), extensively uses all relevant Linux security features/modules (more than any other), and actually helps to stop LPE by re-implementing or denying dangerous syscalls like in the case of many of the recent vulnerabilities. Biggest caveat is that it’s not for beginners, even though it abstracts a lot of the complexity. I’d also neverbrun malware in just a sandbox, but use that alongside a proper VM.
TL;DR
No sandbox will save you from good malware. Firejail might be enough for script kiddies, but could make your system more vulnerable to privilege escalation attacks. Avoid installing things you don’t need.
Things sandboxed by Firejail share the same host kernel. Therefore, kernel vulnerabilities could allow for privilege escalation.
Firejail itself is a security-hole. It is a massive root SetUID binary which can and has been used for privilege escalation. I avoid it entirely. Unprivileged sandboxes are better, but lack the built-in profiles provided by Firejail.
If I was trying to sandbox malware, I would use sydbox. It is memory safe (unlike Firejail or Bubblewrap), unprivileged (unlike Firejail), secure sandbox by default (unlike Bubblewrap), extensively uses all relevant Linux security features/modules (more than any other), and actually helps to stop LPE by re-implementing or denying dangerous syscalls like in the case of many of the recent vulnerabilities. Biggest caveat is that it’s not for beginners, even though it abstracts a lot of the complexity. I’d also neverbrun malware in just a sandbox, but use that alongside a proper VM.
TL;DR No sandbox will save you from good malware. Firejail might be enough for script kiddies, but could make your system more vulnerable to privilege escalation attacks. Avoid installing things you don’t need.