CVE-2024-22911

What it actually does

Stack buffer underflow in parseExpression during expression parsing leads to memory corruption with potential for crashes or arbitrary code execution on the local system.

Why it matters to the business

Local attackers can compromise systems that process untrusted input files with SWFTools, risking unauthorized code execution, data loss, or denial of service in environments still relying on the outdated tool.

How an attack unfolds

An attacker supplies a crafted input file containing a malformed expression to the swfc utility; when parseExpression processes the input, the underflow corrupts adjacent stack memory, enabling control-flow hijacking or crash.

How to fix it

Remove or isolate the vulnerable SWFTools 0.9.2 installation; replace with a newer maintained alternative or rebuild from source after applying upstream fixes if released.

How to confirm the fix worked

Confirm the presence of the vulnerable parseExpression function at src/swfc.c:2602 via source inspection or binary analysis, then test with known triggering inputs to verify crashes or corruption are eliminated after mitigation.

Typical attack path

1. Identify or generate a malformed expression that triggers the underflow in parseExpression
2. Invoke swfc or related SWFTools binaries on the malicious file
3. Trigger memory corruption to achieve code execution or denial of service

How to detect it

Review process crash logs and core dumps for swfc or swftools binaries; correlate file-access events involving SWF or related inputs immediately preceding abnormal termination.

What your security team should do

• Inventory all systems using SWFTools and remove or restrict access to the vulnerable binary
• Block execution of swfc and related tools on endpoints that handle untrusted files
• Monitor vendor or community channels for any future patched releases