CVE-2020-37124: 4mhz b64dec

Critical severity, CVSS 9.8. EPSS: 0.4% chance of exploitation in the next 30 days.

B64dec 1.1.2 contains a buffer overflow vulnerability that allows attackers to execute arbitrary code by overwriting Structured Exception Handler (SEH) with crafted input. Attackers can leverage an egg hunter technique and carefully constructed payload to inject and execute malicious code during base64 decoding process.

Affected products

• 4mhz b64dec: version 1.1.2 only

Published 2026-02-05. Last modified 2026-06-17.