CVE-2021-26711Public exploitNetwork attack vector

External content rendering via unchecked help URL

Published Feb 5, 2021 · Updated Aug 3, 2024

Frame injection in Redwood Report2Web 4.3.4.5 allows remote attackers to render external content in the online help frame. The help/Online_Help/NetHelp/default.htm page accepts the turl parameter as the frame's external resource without constraining its destination. No authentication or user interaction is required; the demonstrated consequence is limited to attacker-chosen content rendered in the help frame.

CVSS severity5.3
Medium
EPSS probability1.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Frame injection in Redwood Report2Web 4.3.4.5 allows remote attackers to render external content in the online help frame. The help/Online_Help/NetHelp/default.htm page accepts the turl parameter as the frame's external resource without constraining its destination. No authentication or user interaction is required; the demonstrated consequence is limited to attacker-chosen content rendered in the help frame.

The record

CVE
CVE-2021-26711
Published
Feb 5, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-610
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 5, 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

5.3NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.0NVDAV:N/AC:L/Au:N/C:N/I:P/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

CWE-610Externally Controlled Reference to a Resource in Another Sphere

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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