No exploitation reportedFix available

CVE-2021-31474

Q: Is CVE-2021-31474 actively exploited?

Active exploitation of CVE-2021-31474 has not been confirmed. Its EPSS score was 93.9% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-31474?

CVE-2021-31474 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2021-05-21
Fixed in2020.2.5
WeaknessCWE-502

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of SolarWinds Network Performance Monitor 2020.2.1. Authentication is not required to exploit this vulnerability. The specific flaw exists within the SolarWinds.Serialization library. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of SYSTEM. Was ZDI-CAN-12213.

Timeline

dates in UTC

2021-05-2115:15CVE publishedNVD
2026-10-2319:23EPSS crossed 10 %FIRST EPSS

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-31474?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-31474?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Solarwinds network performance monitor

Branch	Affected	Fixed in	Source
2020.2	≥ 2020.2.1, < 2020.2.5	2020.2.5	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Solarwinds network performance monitor to 2020.2.5

Advisories and patches

documentation.solarwinds.comRelease Notes · Vendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.19.8read 2026-10-23
CNACVSS 3.09.8read 2026-10-23
NVDCVSS 2.010read 2026-10-23
CNAweakness (CWE)CWE-502read 2026-10-23
FIRST EPSSEPSS score93.9 %read 2026-10-23

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2021-05-21
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-31474?

Is CVE-2021-31474 actively exploited?

Active exploitation of CVE-2021-31474 has not been confirmed. Its EPSS score was 93.9% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-31474?

CVE-2021-31474 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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