# CVE-2026-28305: SolarWinds Serv-U IDOR remote code execution as root

Source: https://junglewise.ai/threats/cve-2026-28305-solarwinds-serv-u-idor-remote-code-execution-as-root  
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-2026-28305 · 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 could allow an administrative user to take full control of the underlying server. By exploiting an authorization bypass, an attacker with specific directory access can execute commands with the highest level of system privileges (root). This could lead to a complete compromise of the server, including the theft or deletion of sensitive files and the disruption of file transfer services.

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

## Quick answers

**Is CVE-2026-28305 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-28305 being exploited in the wild.

**How severe is CVE-2026-28305?** 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-2026-28305?** 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-2026-28305 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-28305?** 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

An Insecure Direct Object Reference (IDOR) vulnerability (CWE-639) exists in SolarWinds Serv-U versions 15.5.4 HF1 and earlier. The flaw allows an attacker to bypass authorization by manipulating user-controlled keys to access or modify objects they should not have permission to reach. To exploit this, an attacker requires a domain account with administrative privileges and both read and write access to the home directory. Successful exploitation allows for remote code execution with root privileges on Linux deployments, though the impact is reportedly lower on Windows systems. The vulnerability is addressed in Serv-U version 2026.3.

## 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-2026-28305](https://www.solarwinds.com/trust-center/security-advisories/CVE-2026-28305)

## 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)