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CVE-2020-37056 (GCVE-0-2020-37056)

Vulnerability from cvelistv5 – Published: 2026-01-30 22:07 – Updated: 2026-07-28 01:47
VLAI
Title
Crystal Shard http-protection 0.2.0 - IP Spoofing Bypass
Summary
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.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-02 20:07 UTC
CWE
  • CWE-290 - Authentication Bypass by Spoofing
Assigner
References
Impacted products
Vendor Product Version CPE status
Crystal Shard http-protection Affected: <= 0.2.0
    cpe:2.3:a:avg:protection:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2020-05-28 00:00
Credits
Halis Duraki (@0xduraki)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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