CVE-2021-44331

What it actually does

Buffer overflow in encode_ise() function of ARM astcenc 3.2.0 allowing memory corruption with potential for arbitrary code execution.

Why it matters to the business

Attackers may gain full control of systems that process untrusted texture files with the vulnerable encoder, risking data theft or ransomware deployment on developer and build machines.

How an attack unfolds

An attacker crafts a malicious ASTC texture file that triggers the buffer overflow inside encode_ise() when the file is fed to astcenc 3.2.0; because an exploit is publicly available, the crafted file can be delivered via email, download, or supply-chain artifact to achieve code execution.

How to fix it

Upgrade ARM astcenc to the latest available version that resolves the encode_ise() buffer overflow; if no fixed release exists, replace the encoder with a maintained alternative and avoid processing untrusted texture assets.

How to confirm the fix worked

Confirm astcenc version is not 3.2.0; run the encoder against known-good and fuzz-generated inputs while monitoring for crashes or sanitizer violations in encode_ise().

Typical attack path

1. Obtain or generate a malicious ASTC texture input designed to overflow encode_ise()
2. Invoke astcenc 3.2.0 locally with the crafted file (requires user interaction)
3. Trigger memory corruption leading to arbitrary code execution

How to detect it

Review process execution logs and crash dumps for astcenc invocations that terminate abnormally; correlate with file-creation timestamps of ASTC assets from untrusted sources.

What your security team should do

• Immediately inventory all uses of astcenc 3.2.0 and block execution on untrusted inputs
• Replace vulnerable encoder with a patched or alternative implementation
• Add file-type sandboxing and integrity checks for texture assets in build pipelines