How severe is CVE-2021-25274?

CVE-2021-25274 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-25274 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 36% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25274?

CVE-2021-25274 affects Solarwinds Orion Platform. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25274?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-25274 published?

CVE-2021-25274 was published on 2021-02-03 and last updated on 2026-06-17.

CVE-2021-25274

CVE-2021-25274 is a critical-severity vulnerability in Solarwinds Orion Platform with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 36% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 36% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Solarwinds Orion Platform
Published: 2021-02-03
Last modified: 2026-06-17

Description

The Collector Service in SolarWinds Orion Platform before 2020.2.4 uses MSMQ (Microsoft Message Queue) and doesn't set permissions on its private queues. As a result, remote unauthenticated clients can send messages to TCP port 1801 that the Collector Service will process. Additionally, upon processing of such messages, the service deserializes them in insecure manner, allowing remote arbitrary code execution as LocalSystem.

Frequently asked questions

What is CVE-2021-25274?: The Collector Service in SolarWinds Orion Platform before 2020.2.4 uses MSMQ (Microsoft Message Queue) and doesn't set permissions on its private queues. As a result, remote unauthenticated clients can send messages to TCP port 1801 that the Collector Service will process. Additionally, upon processing of such messages, the service deserializes them in insecure manner, allowing remote arbitrary code execution as LocalSystem.
How severe is CVE-2021-25274?: CVE-2021-25274 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-25274 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 36% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25274?: CVE-2021-25274 affects Solarwinds Orion Platform. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25274?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-25274 published?: CVE-2021-25274 was published on 2021-02-03 and last updated on 2026-06-17.

References

https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/full-system-control-with-new-solarwinds-orion-based-and-serv-u-ftp-vulnerabilities/

Affected products (1)

cpe:2.3:a:solarwinds:orion_platform:*:*:*:*:*:*:*:*

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