Stack-Based Buffer Overflow in Ritlabs TinyWeb Server Affects Win32 Systems
CVE-2026-12200

6.9MEDIUM

Key Information:

Vendor

Ritlabs

Status
Tinyweb Server
Vendor
CVE Published:
15 June 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-12200?

A vulnerability has been identified in Ritlabs TinyWeb Server, specifically in the libeay32.dll.html component related to the Header Handler. This issue allows attackers to exploit an unknown function by manipulating the Authorization argument, leading to a stack-based buffer overflow. The potential for remote exploitation emphasizes the critical need for users to take immediate action. Despite early disclosure efforts, the vendor has not responded, leaving users potentially vulnerable to this public exploit.

Affected Version(s)

TinyWeb Server 1.0

TinyWeb Server 1.1

TinyWeb Server 1.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-12200 - Proof of Concept

References

https://vuldb.com/vuln/370842
vdb-entrytechnical-description
https://vuldb.com/vuln/370842/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-12200
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

nathan2 (VulDB User)
VulDB CNA Team
.