High

Sandbox Escape via .Xauthority Symlink in Firejail

IdentifiersCVE-2017-5180CWE-59

A vulnerability in Firejail before versions 0.9.44.4 and 0.9.38.8 LTS allows local users to escape the sandbox by exploiting improper handling of the .Xauthority file. The flaw is due to Firejail not properly considering the case of the .Xauthority file when attempting to prevent access to user files with an effective UID of zero. Attackers can leverage a symlink and the --private option to gain unauthorized access outside the sandbox.

For your environment

Are you exposed to this one?

Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.

Start free trial

ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows a local attacker to escape the Firejail sandbox, potentially gaining unauthorized access to files and resources outside the intended sandboxed environment. This could lead to privilege escalation or compromise of sensitive data.

Mitigation

If you can’t patch tonight, do this now.

As a temporary mitigation, restrict local user access to the system and avoid using the --private option with untrusted applications until the vulnerable Firejail version is upgraded.

Remediation

Patch, then assume compromise.

Upgrade Firejail to version 0.9.44.4 or later, or for the LTS branch, to version 0.9.38.8 LTS or later, where the issue has been addressed.

PUBLIC EXPLOITS

Exploits

No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.

VALID 0 / 1 TOTALView more in app

All candidate exploits were filtered out by Mallory's validation.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

Firejail ProjectFirejailapplication

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

No public activity tracked yet. Mallory keeps watching.

0 SOURCESView more in app

No public activity observed for this vulnerability.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.

Start free trial

Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity