CVE-2026-22781

TinyWeb is a web server (HTTP, HTTPS) written in Delphi for Win32. TinyWeb HTTP Server before version 1.98 is vulnerable to OS command injection via CGI ISINDEX-style query parameters. The query parameters are passed as command-line arguments to the CGI executable via Windows CreateProcess(). An unauthenticated remote attacker can execute arbitrary commands on the server by injecting Windows shell metacharacters into HTTP requests. This vulnerability is fixed in 1.98.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/maximmasiutin/TinyWeb/commit/876b7e2887f4ea5be3e18bb2af7313f23a283c96	Patch
https://github.com/maximmasiutin/TinyWeb/security/advisories/GHSA-m779-84h5-72q2	Third Party Advisory
https://www.masiutin.net/tinyweb-cve-2025-cgi-command-injection.html	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:ritlabs:tinyweb:*:*:*:*:*:*:*:*

History

16 Jan 2026, 18:44

Type	Values Removed	Values Added
CPE		cpe:2.3:a:ritlabs:tinyweb::::::::
References	~~() https://github.com/maximmasiutin/TinyWeb/commit/876b7e2887f4ea5be3e18bb2af7313f23a283c96 -~~	() https://github.com/maximmasiutin/TinyWeb/commit/876b7e2887f4ea5be3e18bb2af7313f23a283c96 - Patch
References	~~() https://github.com/maximmasiutin/TinyWeb/security/advisories/GHSA-m779-84h5-72q2 -~~	() https://github.com/maximmasiutin/TinyWeb/security/advisories/GHSA-m779-84h5-72q2 - Third Party Advisory
References	~~() https://www.masiutin.net/tinyweb-cve-2025-cgi-command-injection.html -~~	() https://www.masiutin.net/tinyweb-cve-2025-cgi-command-injection.html - Third Party Advisory
First Time		Ritlabs tinyweb Ritlabs
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8

12 Jan 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-12 19:16

Updated : 2026-01-16 18:44

NVD link : CVE-2026-22781

Mitre link : CVE-2026-22781

CVE.ORG link : CVE-2026-22781

JSON object : View

Products Affected

ritlabs

tinyweb

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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