# CVE-2026-28306: SolarWinds Serv-U privilege escalation in domain administration

Source: https://junglewise.ai/threats/cve-2026-28306-solarwinds-serv-u-privilege-escalation-in-domain-administration  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-21. Updated: 2026-07-21  
License: CC BY 4.0 with a link back

CVE-2026-28306 · Severity: critical · CVSS 9.1 · Published 2026-07-21

SolarWinds Serv-U, a managed file transfer and FTP server, is affected by a security flaw that allows certain administrative users to gain full control over the entire system. A domain administrator can exploit this vulnerability to elevate their access to system administrator status, potentially leading to unauthorized access to sensitive files and configuration settings. This issue is particularly severe in non-Windows environments, though Windows deployments are also impacted to a lesser degree.

Technologies: [SolarWinds Serv-U](https://junglewise.ai/threats/technologies/serv-u). Vendors: [SolarWinds](https://junglewise.ai/threats/vendors/solarwinds).

## Quick answers

**Is CVE-2026-28306 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-28306 being exploited in the wild.

**How severe is CVE-2026-28306?** Critical severity, with a CVSS score of 9.1, published 21 July 2026.

**Which products and versions are affected?** SolarWinds Serv-U 15.5.4 HF1 and below.

**Is there a fix for CVE-2026-28306?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-28306 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-28306?** Check whether you run SolarWinds Serv-U at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A privilege escalation vulnerability (CWE-284: Improper Access Control) exists in SolarWinds Serv-U versions 15.5.4 HF1 and earlier. The flaw allows an authenticated attacker with domain administrator privileges to bypass access controls and elevate their permissions to system administrator level. The attack vector is network-based and requires high privileges to initiate, but it results in a scope change (S:C) allowing full compromise of the application environment. SolarWinds has addressed this in the Serv-U 2026.3 release.

## Affected products

- SolarWinds Serv-U 15.5.4 HF1 and below

## Timeline

- 2026-07-21: disclosed
- 2026-07-21: advisory

## References

- [https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_2026-3_release_notes.htm](https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_2026-3_release_notes.htm)
- [https://www.solarwinds.com/trust-center/security-advisories/CVE-2026-28306](https://www.solarwinds.com/trust-center/security-advisories/CVE-2026-28306)

## Related threats

- [SolarWinds Serv-U broken access control privilege escalation](https://junglewise.ai/threats/cve-2026-28321-solarwinds-serv-u-broken-access-control-privilege-escalation)
- [SolarWinds Serv-U privilege escalation via IDOR](https://junglewise.ai/threats/cve-2026-28317-solarwinds-serv-u-privilege-escalation-via-idor)
- [SolarWinds Serv-U IDOR privilege escalation to root](https://junglewise.ai/threats/cve-2026-28316-solarwinds-serv-u-idor-privilege-escalation-to-root)
- [SolarWinds Serv-U stored XSS in administrator interface](https://junglewise.ai/threats/cve-2026-28315-solarwinds-serv-u-stored-xss-in-administrator-interface)
- [SolarWinds Serv-U account takeover via IDOR](https://junglewise.ai/threats/cve-2026-28314-solarwinds-serv-u-account-takeover-via-idor)