Vulnerability · Published Feb 5, 2026 · Assigned by VulnCheck
CVE-2020-37124B64dec 1.1.2 - Buffer Overflow (SEH Overflow + Egg Hunter)
Critical 9.8
In plain English
A critical-severity stack buffer overflow in B64dec from 4Mhz. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 36% of all known vulnerabilities).
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.4%top 63.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
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 (as reported)
Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- ExploitDB-48317 exploit
- Product Webpage product
- VulnCheck Advisory: B64dec 1.1.2 - Buffer Overflow (SEH Overflow + Egg Hunter) third-party-advisory