How severe is CVE-2026-28321?

CVE-2026-28321 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-28321 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-28321?

CVE-2026-28321 affects Solarwinds Serv-u. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-28321?

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-2026-28321 published?

CVE-2026-28321 was published on 2026-07-21 and last updated on 2026-07-24.

CVE-2026-28321

CVE-2026-28321 is a critical-severity vulnerability in Solarwinds Serv-u with a CVSS 3.x base score of 9.1. 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-284.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Solarwinds Serv-u
Published: 2026-07-21
Last modified: 2026-07-24

Description

SolarWinds Serv-U is affected by a broken access control vulnerability that could allow arbitrary file read and write, which can then be used to escalate privileges and execute code as root. A domain administrator access is required, and the impact is lower in Windows installations.

Frequently asked questions

What is CVE-2026-28321?: SolarWinds Serv-U is affected by a broken access control vulnerability that could allow arbitrary file read and write, which can then be used to escalate privileges and execute code as root. A domain administrator access is required, and the impact is lower in Windows installations.
How severe is CVE-2026-28321?: CVE-2026-28321 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-28321 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-28321?: CVE-2026-28321 affects Solarwinds Serv-u. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-28321?: 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-2026-28321 published?: CVE-2026-28321 was published on 2026-07-21 and last updated on 2026-07-24.

References

Affected products (1)

cpe:2.3:a:solarwinds:serv-u:*:*:*:*:*:*:*:*

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