CVE-2024-57850

What it actually does

The rtime decompression routine in jffs2 lacks complete bounds checking during decompression, allowing memory corruption outside the decompression buffer when processing corrupted compressed data.

Why it matters to the business

Potential system instability, crashes, or unauthorized code execution on Linux systems using JFFS2 file systems, increasing risk of data loss or compromise especially in embedded or storage-heavy environments.

How an attack unfolds

An attacker supplies specially crafted corrupted compressed data to trigger the jffs2 rtime decompression path, bypassing bounds checks to corrupt adjacent memory regions and achieve code execution or denial of service. Listed threat actors in Linux kernel campaigns may leverage similar out-of-bounds issues.

How to fix it

Apply kernel updates that include the bounds check fix for jffs2 rtime decompression. For listed chromium-browser packages on Ubuntu 14.04 LTS, upgrade to version 58.0.3029.81-0ubuntu0.14.04.1172 or later.

How to confirm the fix worked

Verify presence of updated kernel sources or packages containing the bounds check in the rtime decompression function; test decompression of malformed data to confirm no memory corruption occurs.

Typical attack path

1. Identify target systems using JFFS2 with rtime compression
2. Deliver malformed compressed data via file system operations or network
3. Trigger decompression routine to induce out-of-bounds write
4. Exploit resulting memory corruption for privilege escalation or persistence

How to detect it

Inspect kernel logs and file system access logs for anomalies during decompression of JFFS2 data; look for signs of memory faults or unexpected crashes tied to rtime routines. Correlate with threat actor patterns in Linux kernel out-of-bounds exploits.

What your security team should do

• Prioritize patching affected Linux kernels with JFFS2 support
• Monitor EPSS trend for any increase indicating rising exploit interest
• Review systems for JFFS2 usage and apply fixed package versions where applicable
• Harden file system handling to reject suspicious compressed data