CVE-2021-20785Network attack vector

Script execution in administrator sessions via crafted request

Published Jul 28, 2021 · Updated Aug 3, 2024

Cross-site scripting in GroupSession before 5.1.0 allows remote attackers to execute scripts through a crafted request. The vendor has not disclosed the affected URL or the input-handling operation that places request data into an executable page context. Execution requires an administrator to be logged in when the crafted request reaches the specified URL, exposing that browser session to arbitrary script execution.

CVSS severity6.1
Medium
EPSS probability0.60%
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 GroupSession before 5.1.0 allows remote attackers to execute scripts through a crafted request. The vendor has not disclosed the affected URL or the input-handling operation that places request data into an executable page context. Execution requires an administrator to be logged in when the crafted request reaches the specified URL, exposing that browser session to arbitrary script execution.

The record

CVE
CVE-2021-20785
Published
Jul 28, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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

2.6JVNAV:N/AC:H/Au:N/C:N/I:P/A:N
6.1JVNCVSS:3.0/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

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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