# CVE-2026-28308: SolarWinds Serv-U IDOR remote code execution

Source: https://junglewise.ai/threats/cve-2026-28308-solarwinds-serv-u-idor-remote-code-execution  
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-2026-28308 · 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 attacker to take full control of the server. To exploit this, an attacker must already have domain administrator privileges within the application. While the risk is lower for Windows-based installations, a successful attack could lead to unauthorized access to sensitive files, data theft, or a complete service shutdown.

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

## Quick answers

**Is CVE-2026-28308 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-28308 being exploited in the wild.

**How severe is CVE-2026-28308?** 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-2026-28308?** A patch was published on 2026-07-21: Fixed in Serv-U 2026.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-28308 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-28308?** 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

SolarWinds Serv-U contains an Insecure Direct Object Reference (IDOR) vulnerability (CWE-639) that facilitates remote code execution (RCE). The vulnerability exists due to improper authorization checks when accessing internal objects, allowing a user to manipulate identifiers to gain unauthorized access to system functions. Exploitation requires the attacker to possess high privileges (Domain Administrator). The impact is reportedly lower in Windows deployments compared to other operating systems. The issue is resolved in Serv-U version 2026.3.

## Affected products

- SolarWinds Serv-U 15.5.4 HF1 and below

## Timeline

- 2026-07-21: advisory: Initial advisory published by SolarWinds
- 2026-07-21: patched: Fixed in Serv-U 2026.3

## 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-2026-28308](https://www.solarwinds.com/trust-center/security-advisories/CVE-2026-28308)

## 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)