Is this vulnerability remotely exploitable?

Yes. An attacker who can reach the TinyWeb HTTP/HTTPS service can send crafted requests with malicious headers to trigger the issue, without needing local access.

Does exploitation require authentication or a specific user role?

Not necessarily. The vulnerable behavior occurs during HTTP header parsing, which is typically performed before authentication. However, in some deployments, only authenticated endpoints may expose specific CGI scripts that make exploitation more impactful.

What is the safest general fix pattern?

The safest fix is to implement strict, centralized header validation that rejects any header line or value containing control characters (including encoded forms) before mapping them to CGI environment variables or other internal representations. Additionally, CGI scripts should treat all environment-derived values as untrusted input.

Severity:

HIGH RISK

(8.2)

Improper Input Validation of HTTP Headers (CWE-20) in TinyWeb CGI Environment Mapping

CVE-2026-29046

Published:

Mar 5, 2026

Status:

Analyzed

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

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Vulnerability Type

Category:

Improper Input Validation

CWE:

CWE-20;CWE-74;CWE-93;CWE-114

Impact:

CGI Environment Manipulation and Header Injection

Severity:

HIGH RISK

(8.2)

CVSS Version:

3.1

Vulnerability Type

Category:

Improper Input Validation

CWE:

CWE-20;CWE-74;CWE-93;CWE-114

Impact:

CGI Environment Manipulation and Header Injection

Severity:

HIGH RISK

(8.2)

CVSS Version:

3.1

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Improper Input Validation of HTTP Headers (CWE-20) in TinyWeb CGI Environment Mapping

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

HIGH RISK

HIGH

(8.6)

Server-Side Request Forgery (CWE-918) in OpenClaw Zalo Plugin sendPhoto

HIGH RISK

HIGH

(8.8)

Authorization Bypass (CWE-863) in OpenClaw Matrix Room Control Commands

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

Ship clean & secure code faster

Ship clean & secure code faster

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