iwasm vulnerable to filesystem sandbox escape with symlink when using uvwasi feature

Scope

What the vendor says is affected

• cbl2 fluent-bit 3.0.6-2
• azl3 fluent-bit 3.1.9-4 on Azure Linux 3.0
• cbl2 fluent-bit 3.0.6-2 on CBL-Mariner 2.0

Timeline

When this advisory changed

1. Aug 12, 2026 at 10:34 PM UTC
   Published by Microsoft Security Response Center

   The publication date reported by the vendor.

2. Sep 28, 2026 at 11:20 AM UTC
   Added to SecurityAlert

   We collected the advisory from the official source.

Vulnerabilities

CVEs named in this advisory

CVE-2025-43853View CVSS, KEV, EPSS, and threat context