CVE-2019-25634

HIGH EPSS 17.5%
Published Mar 24, 20263mo ago · Modified Jun 17, 20261w ago
8.6 CVSS 4.0
High
Find Similar
Published Mar 24, 2026 3mo ago
Last Modified Jun 17, 2026 1w ago

Description

Base64 Decoder 1.1.2 contains a stack-based buffer overflow vulnerability that allows local attackers to execute arbitrary code by triggering a structured exception handler (SEH) overwrite. Attackers can craft a malicious input file that overflows a buffer, overwrites the SEH chain with a POP-POP-RET gadget address, and uses an egghunter payload to locate and execute shellcode for code execution.

CVSS Details

Base Score
8.6
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Local
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
17.5% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available

Weaknesses 1

CWE-787 Out-of-bounds Write Memory Safety

Affected Products 1

VendorProductVersionRange
4mhzbase64_decoder1.1.2any

References 4

  • 4mhz.de http://4mhz.de/b64dec.html
    ProductRelease Notes
  • 4mhz.de http://4mhz.de/download.php?file=b64dec-1-1-2.zip
    Product
  • exploit-db.com https://www.exploit-db.com/exploits/46625
    Exploit
  • vulncheck.com https://www.vulncheck.com/advisories/base64-decoder-local-buffer-overflow-seh-egghunter
    Third Party Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.