Broadcom VMware ESX
CVE-2026-41709
Broadcom VMWare ESX contains an insufficient logging vulnerability that could allow a malicious actor with admin access to perform certain operations without being logged.
What this means for your business
- It affects Broadcom VMware ESX. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 28 October 2026.
- FIRST's prediction model gives it a 0.7% chance of attack attempts being seen in the next 30 days, ranking above 52% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Broadcom VMware ESX.
- 2If you do, follow CISA's required action below. No patch reference has been published yet.
- 3Treat it as urgent. US federal agencies must fix it by 11 November 2026. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Fastnexa security experts
Attackers are already using this flaw. Is your Broadcom VMware ESX exposed?
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Required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA’s wording, unedited. The notes it mentions are in CISA’s catalogue entry.
Scoring
- CVSS
- Not yet scored
Dates
- Published
- 2026-10-28
- Added to KEV
- 2026-10-28
- Remediation due
- 2026-11-11
- Sources
- CISA KEV
Coverage
- Chinese Hackers Quietly Used Low-Severity ESXi Logging Flaw as Zero-DaySecurityWeek · 2026-10-29
- China-Linked Hackers Exploited VMware ESX Zero-Day to Reduce Audit Trail VisibilityThe Hacker News · 2026-10-29
- VMware security advisory (AV26-763) – Update 2Canadian Centre for Cyber Security · 2026-10-28