CVE-2019-25634

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 v3 8.4 HIGH

8.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.5 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
http://4mhz.de/b64dec.html
http://4mhz.de/download.php?file=b64dec-1-1-2.zip
https://www.exploit-db.com/exploits/46625
https://www.vulncheck.com/advisories/base64-decoder-local-buffer-overflow-seh-egghunter

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-24 12:16

Updated : 2026-03-24 15:53

NVD link : CVE-2019-25634

Mitre link : CVE-2019-25634

CVE.ORG link : CVE-2019-25634

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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