How severe is CVE-2021-27277?

CVE-2021-27277 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27277 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27277?

CVE-2021-27277 affects Solarwinds Orion Platform. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27277?

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-2021-27277 published?

CVE-2021-27277 was published on 2021-04-22 and last updated on 2026-06-17.

CVE-2021-27277

CVE-2021-27277 is a high-severity vulnerability in Solarwinds Orion Platform with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 7.2
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Solarwinds Orion Platform
Published: 2021-04-22
Last modified: 2026-06-17

Description

This vulnerability allows local attackers to escalate privileges on affected installations of SolarWinds Orion Virtual Infrastructure Monitor 2020.2. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the OneTimeJobSchedulerEventsService WCF service. 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 escalate privileges and execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-11955.

Frequently asked questions

What is CVE-2021-27277?: This vulnerability allows local attackers to escalate privileges on affected installations of SolarWinds Orion Virtual Infrastructure Monitor 2020.2. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the OneTimeJobSchedulerEventsService WCF service. 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 escalate privileges and execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-11955.
How severe is CVE-2021-27277?: CVE-2021-27277 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27277 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27277?: CVE-2021-27277 affects Solarwinds Orion Platform. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27277?: 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-2021-27277 published?: CVE-2021-27277 was published on 2021-04-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:solarwinds:orion_platform:2020.2:*:*:*:*:*:*:*

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