CVE-2026-28321

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreHIGH confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-21. a secondary CVSS source baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

SolarWinds Serv-U is affected by a broken access control vulnerability that could allow arbitrary file read and write, which can then be used to escalate privileges and execute code as root. A domain administrator access is required, and the impact is lower in Windows installations.

CVSS v3
9.1
EG Score
9.1(high)
EG Risk
41(Track)
EG Risk 41/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity91% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
34%
KEV
Not listed

Published

July 21, 2026

Last Modified

July 24, 2026

Advisory Details (2)

Auto-updated Jul 21, 2026
No patch confirmed yet.
generic

SolarWinds Trust Center Security Advisories | CVE-2026-28321

https://www.solarwinds.com/trust-center/security-advisories/CVE-2026-28321
generic

Serv-U 2026.3 release notes

https://documentation.solarwinds.com/en/success_center/servu/content/release_notes/servu_2026-3_release_notes.htm

Vendor Advisories for CVE-2026-28321(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 45× in last 7d / 54× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-30 21:39 UTCGHSA enrichment
  2. 2026-07-30 17:43 UTCEG score recompute
  3. 2026-07-30 17:42 UTCGHSA enrichment
  4. 2026-07-30 16:27 UTCEPSS rescore
  5. 2026-07-30 13:48 UTCGHSA enrichment
  6. 2026-07-30 09:53 UTCEG score recompute
  7. 2026-07-30 09:53 UTCGHSA enrichment
  8. 2026-07-30 06:01 UTCGHSA enrichment
  9. 2026-07-30 02:09 UTCEG score recompute
  10. 2026-07-30 02:09 UTCGHSA enrichment
  11. 2026-07-30 01:30 UTCEPSS rescore
  12. 2026-07-29 22:17 UTCGHSA enrichment
  13. 2026-07-29 18:26 UTCGHSA enrichment
  14. 2026-07-29 14:34 UTCGHSA enrichment
  15. 2026-07-29 10:43 UTCGHSA enrichment
  16. 2026-07-29 06:51 UTCGHSA enrichment
  17. 2026-07-29 02:58 UTCGHSA enrichment
  18. 2026-07-28 23:07 UTCGHSA enrichment
  19. 2026-07-28 19:01 UTCEG score recompute
  20. 2026-07-28 19:01 UTCGHSA enrichment
  21. 2026-07-28 15:36 UTCEPSS rescore
  22. 2026-07-28 15:07 UTCGHSA enrichment
  23. 2026-07-28 11:14 UTCGHSA enrichment
  24. 2026-07-28 07:16 UTCGHSA enrichment
  25. 2026-07-28 03:22 UTCGHSA enrichment
Show 29 more
  1. 2026-07-27 23:29 UTCGHSA enrichment
  2. 2026-07-27 19:10 UTCGHSA enrichment
  3. 2026-07-27 15:13 UTCEG score recompute
  4. 2026-07-27 15:13 UTCGHSA enrichment
  5. 2026-07-27 09:53 UTCGHSA enrichment
  6. 2026-07-27 06:02 UTCGHSA enrichment
  7. 2026-07-27 02:06 UTCGHSA enrichment
  8. 2026-07-26 22:15 UTCGHSA enrichment
  9. 2026-07-26 18:24 UTCEG score recompute
  10. 2026-07-26 18:24 UTCGHSA enrichment
  11. 2026-07-26 14:54 UTCEPSS rescore
  12. 2026-07-26 14:54 UTCEPSS rescore
  13. 2026-07-26 14:22 UTCGHSA enrichment
  14. 2026-07-26 10:30 UTCEG score recompute
  15. 2026-07-26 10:30 UTCGHSA enrichment
  16. 2026-07-26 04:21 UTCEG score recompute
  17. 2026-07-26 04:20 UTCGHSA enrichment
  18. 2026-07-25 14:18 UTCEPSS rescore
  19. 2026-07-25 14:17 UTCEPSS rescore
  20. 2026-07-24 14:17 UTCEPSS rescore
  21. 2026-07-23 03:08 UTCEG score recompute
  22. 2026-07-22 14:08 UTCEPSS rescore
  23. 2026-07-22 14:08 UTCEPSS rescore
  24. 2026-07-21 20:43 UTCEG score recompute
  25. 2026-07-21 20:42 UTCGHSA enrichment
  26. 2026-07-21 17:40 UTCEG score recompute
  27. 2026-07-21 17:21 UTCEG score recompute
  28. 2026-07-21 16:00 UTCEG score recompute
  29. 2026-07-21 15:58 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-28321?
CVE-2026-28321 is a critical vulnerability published on July 21, 2026. SolarWinds Serv-U is affected by a broken access control vulnerability that could allow arbitrary file read and write, which can then be used to escalate privileges and execute code as root. A domain administrator access is required, and the impact is lower in Windows installations.
When was CVE-2026-28321 disclosed?
CVE-2026-28321 was first published in the National Vulnerability Database on July 21, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-28321 actively exploited?
CVE-2026-28321 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 66.4% of all scored CVEs.
What is the CVSS score of CVE-2026-28321?
CVE-2026-28321 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2026-28321?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-28321, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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