CVE-2021-35244

SYSTEM code execution via arbitrary alert-file write

Published Dec 20, 2021 · Updated Sep 16, 2024

Unrestricted file upload in SolarWinds Platform 2020.2.6 HF2 and earlier allows remote authenticated users to execute code as SYSTEM. The Log alert to a file action accepts user-supplied file data without proper validation and permits writes to any file. Orion alert management rights are required; successful exploitation can place arbitrary files and execute their contents with SYSTEM privileges.

CVSS severity6.8
Medium
EPSS probability5.77%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unrestricted file upload in SolarWinds Platform 2020.2.6 HF2 and earlier allows remote authenticated users to execute code as SYSTEM. The Log alert to a file action accepts user-supplied file data without proper validation and permits writes to any file. Orion alert management rights are required; successful exploitation can place arbitrary files and execute their contents with SYSTEM privileges.

The record

CVE
CVE-2021-35244
Published
Dec 20, 2021
Updated
Sep 16, 2024
Vendor
SolarWinds
Product
SolarWinds Platform
Classifications
CWE-434, T1190
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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 HF 2 and previous versions <2020.2.6 HF 3

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

SolarWinds · SolarWinds Platformversion=2020.2.6 HF 2 and previous versions <2020.2.6 HF 3

Published CVSS scores

8.5NIST NVDAV:N/AC:M/Au:S/C:C/I:C/A:C
6.8SolarWindsCVSS:3.1/AV:A/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:L
7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
T1190Exploit Public-Facing Application

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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