CVE-2020-21506Public exploitNetwork attack vector

Browser script execution via crafted Referer header

Published Oct 5, 2021 · Updated Aug 4, 2024

Cross-site scripting in waimai Super Cms 20150505 allows remote attackers to execute script in a user's browser via a crafted Referer header. The published proof of concept sends quote-breaking script markup in the Referer header to the Config add endpoint, where it is rendered as active browser content. Exploitation requires a victim to load the affected response; the script then executes in that response's web origin and can read or alter browser-accessible data.

CVSS severity6.1
Medium
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in waimai Super Cms 20150505 allows remote attackers to execute script in a user's browser via a crafted Referer header. The published proof of concept sends quote-breaking script markup in the Referer header to the Config add endpoint, where it is rendered as active browser content. Exploitation requires a victim to load the affected response; the script then executes in that response's web origin and can read or alter browser-accessible data.

The record

CVE
CVE-2020-21506
Published
Oct 5, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 5, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1OSVCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1189Drive-by Compromise

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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