CVE-2020-37056

Crystal Shard http-protection 0.2.0 contains an IP spoofing vulnerability that allows attackers to bypass protection middleware by manipulating request headers. Attackers can hardcode consistent IP values across X-Forwarded-For, X-Client-IP, and X-Real-IP headers to circumvent security checks and gain unauthorized access.

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/rogeriozambon/http-protection
https://www.exploit-db.com/exploits/48533
https://www.vulncheck.com/advisories/crystal-shard-http-protection-ip-spoofing-bypass

Configurations

No configuration.

History

No history.

Information

Published : 2026-01-30 23:16

Updated : 2026-02-03 16:44

NVD link : CVE-2020-37056

Mitre link : CVE-2020-37056

CVE.ORG link : CVE-2020-37056

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

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