CVE-2021-27746Network attack vector

Browser script execution through reflected input

Published Oct 21, 2021 · Updated Aug 3, 2024

Reflected XSS in HCL Connections 6.0 allows remote authenticated users to execute script in another user's browser via crafted input. HCL has not published the affected endpoint, parameter, or exact output-encoding failure that reflects the untrusted input into a page. Exploitation requires low-privileged access and victim interaction, and it permits browser-context data access or modification without interrupting the service.

CVSS severity5.4
Medium
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in HCL Connections 6.0 allows remote authenticated users to execute script in another user's browser via crafted input. HCL has not published the affected endpoint, parameter, or exact output-encoding failure that reflects the untrusted input into a page. Exploitation requires low-privileged access and victim interaction, and it permits browser-context data access or modification without interrupting the service.

The record

CVE
CVE-2021-27746
Published
Oct 21, 2021
Updated
Aug 3, 2024
Vendor
HCL Software
Product
HCL Connections
Classifications
CWE-79, T1204.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 21, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion="HCL Connections 6.0"

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

HCL Software · HCL Connectionsversion="HCL Connections 6.0"

Published CVSS scores

3.5NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4NVDCVSS:3.1/AV:N/AC:L/PR:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1204.001User Execution: Malicious Link

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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