CVE-2026-28313
SolarWinds Serv-U Insecure Direct Object Reference (IDOR) Vulnerability
No known exploitation. EPSS puts it in the 40th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
Steps
Written by AI from the record- Check whether your organization runs SolarWinds Serv-U and identify its installed version.
- Upgrade Serv-U to version 2026.3.
- Review who has high-level Serv-U access and remove access that is no longer needed.
- Have IT review email routing and account activity for unexpected changes.
What it is
From the CVE record
SolarWinds Serv-U is affected by an insecure direct object reference (IDOR) vulnerability that can lead to SMTP hijacking leading to arbitrary account takeover. The impact is lower in Windows deployments.
In plain language
Written by AI from the recordSolarWinds Serv-U versions before 2026.3 can let someone who already has high-level access intercept business email and take over user accounts.
High-privilege network-accessible IDOR in SolarWinds Serv-U permits manipulation of internal object references, enabling SMTP hijacking and arbitrary account takeover; impact is reduced on Windows deployments.
If you're affected
- Intercepted business email
- Full user account takeover
- Fraudulent email activity
- Operational disruption
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.5% chance of exploitation activity in the next 30 days, which ranks it in the 40th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
13 events over 3 days, from the signal feeds we watch.
- OpenVAS check addedpatch available, patch available, record updated, record updated
- Patch availablerecord updated
- Patch availablepatch available, published, weakness classified, att&ck mapped, record updated
Affected products
And 1 more affected product. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Scored 9.1 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required HighRequires admin or elevated privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1078Valid Accountshigh confidence
Sources
References in the record
In the news
Watch the software you run.
My Stack ranks new CVEs for your products by real-world exploitation, so the next serious one reaches you without reading every advisory.
We'll flag the next CVE, public exploit or patch for Serv-U, not every advisory.
A free account adds
- The full version matrix and every affected product
- Exploit links, proofs of concept and Metasploit modules
- Email alerts for the products you watch
- The same data over REST API, MCP and CLI