Is this vulnerability remotely exploitable over the internet?

Yes, if the pyLoad HTTP interface is accessible remotely, an attacker can exploit this by sending crafted requests with spoofed Host headers, without needing prior authentication.

Does an attacker need valid credentials or any local account?

No. The flaw exists in how "local" status is determined; a remote attacker can bypass the localhost restriction without logging in, as long as they can reach the service over the network.

What is the safest general fix pattern for this type of issue?

The safest pattern is to remove any reliance on user-controlled headers for authorization decisions and enforce access based on robust, server-side checks—such as binding local-only features to loopback interfaces or requiring strong authentication and authorization for sensitive endpoints.

Severity:

CRITICAL RISK

(9.8)

Authorization Bypass via Host Header Spoofing (CWE-639) in pyLoad ClickNLoad

CVE-2026-33511

Published:

Mar 24, 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

Recent Vulnerabilities

CWE-77;CWE-78

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setGameSpeedCfg CGI Handler

Remote Code Execution on the Router

April 6, 2026

CWE-77;CWE-78

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setFirewallType Handler

Remote Code Execution on Router Firmware

April 6, 2026

Vulnerability Type

Category:

Authorization Bypass

CWE:

CWE-639

Impact:

Remote, unauthenticated access to localhost-restricted functionality with file write and script execution capabilities

Severity:

CRITICAL RISK

(9.8)

CVSS Version:

3.1

Vulnerability Type

Category:

Authorization Bypass

CWE:

CWE-639

Impact:

Remote, unauthenticated access to localhost-restricted functionality with file write and script execution capabilities

Severity:

CRITICAL RISK

(9.8)

CVSS Version:

3.1

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Ask AI for summary of CodeAnt

Authorization Bypass via Host Header Spoofing (CWE-639) in pyLoad ClickNLoad

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

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setGameSpeedCfg CGI Handler

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in Totolink A7100RU setFirewallType Handler

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

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