CVE-2021-35222

User impersonation via reflected Resource.aspx script

Published Aug 31, 2021 · Updated Aug 4, 2024

Reflected XSS in Resource.aspx in SolarWinds Platform before 2020.2.6 HF1 allows attackers to impersonate users via crafted web content. Resource.aspx returns attacker-controlled content without sufficient output neutralization, causing the browser to execute it in the site's origin; the affected parameter and code path are undisclosed. An adjacent-network attacker must induce user interaction, after which injected script can act as that user and reach code execution through Alerts Settings.

CVSS severity8.0
High
EPSS probability2.61%
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 Resource.aspx in SolarWinds Platform before 2020.2.6 HF1 allows attackers to impersonate users via crafted web content. Resource.aspx returns attacker-controlled content without sufficient output neutralization, causing the browser to execute it in the site's origin; the affected parameter and code path are undisclosed. An adjacent-network attacker must induce user interaction, after which injected script can act as that user and reach code execution through Alerts Settings.

The record

CVE
CVE-2021-35222
Published
Aug 31, 2021
Updated
Aug 4, 2024
Vendor
SolarWinds
Product
SolarWinds Platform
Classifications
CWE-79, T1203
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 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?

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

  1. Affected versionversion=2020.2.6 and previous versions <2020.2.6 HF1

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

SolarWinds · SolarWinds Platformversion=2020.2.6 and previous versions <2020.2.6 HF1

Published CVSS scores

8.0SolarWindsCVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:L
9.6NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
4.3NIST NVDAV:N/AC:M/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.

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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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