How severe is CVE-2021-35217?

CVE-2021-35217 has a CVSS 3.x base score of 8.9, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2021-35217 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 74% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35217?

CVE-2021-35217 affects Solarwinds Patch Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-35217?

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

When was CVE-2021-35217 published?

CVE-2021-35217 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-35217

CVE-2021-35217 is a high-severity vulnerability in Solarwinds Patch Manager with a CVSS 3.x base score of 8.9. Its EPSS exploit-prediction score of 74% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 8.9)
CVSS v2: 6.5
EPSS exploit prediction: 74% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Solarwinds Patch Manager
Published: 2021-09-08
Last modified: 2026-06-17

Description

Insecure Deseralization of untrusted data remote code execution vulnerability was discovered in Patch Manager Orion Platform Integration module and reported to us by ZDI. An Authenticated Attacker could exploit it by executing WSAsyncExecuteTasks deserialization of untrusted data.

Frequently asked questions

What is CVE-2021-35217?: Insecure Deseralization of untrusted data remote code execution vulnerability was discovered in Patch Manager Orion Platform Integration module and reported to us by ZDI. An Authenticated Attacker could exploit it by executing WSAsyncExecuteTasks deserialization of untrusted data.
How severe is CVE-2021-35217?: CVE-2021-35217 has a CVSS 3.x base score of 8.9, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2021-35217 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 74% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35217?: CVE-2021-35217 affects Solarwinds Patch Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-35217?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-35217 published?: CVE-2021-35217 was published on 2021-09-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:solarwinds:patch_manager:*:*:*:*:*:*:*:*

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