CVE-2026-28312Network attack vector

Authenticated group-to-system-administrator escalation enabling root code execution

Published Jul 21, 2026 · Updated Jul 21, 2026

Improper authorization in SolarWinds Serv-U 15.5.4 HF1 and earlier allows remote authenticated users to gain system administrator access. SolarWinds has not disclosed which group-management locus makes the improper authorization decision or which crafted request reaches it. High privileges over the network are required; successful exploitation enables root code execution on Linux, while the lower Windows impact is undisclosed.

CVSS severity9.1
Critical
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in SolarWinds Serv-U 15.5.4 HF1 and earlier allows remote authenticated users to gain system administrator access. SolarWinds has not disclosed which group-management locus makes the improper authorization decision or which crafted request reaches it. High privileges over the network are required; successful exploitation enables root code execution on Linux, while the lower Windows impact is undisclosed.

The record

CVE
CVE-2026-28312
Published
Jul 21, 2026
Updated
Jul 21, 2026
Vendor
SolarWinds
Product
Serv-U
Classifications
CWE-285, CAPEC-233, T1068
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jul 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=15.5.4 HF1 and below

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

SolarWinds · Serv-Uversion=15.5.4 HF1 and below

Published CVSS scores

9.1SolarWindsCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
4.7SolarWindsCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-285Improper Authorization
CAPEC-233Privilege Escalation
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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