Patch tracker / CVE reference / CVE-2026-42833
CVE-2026-42833
Updated July 21, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Critical severity Microsoft vulnerability, CVSS 9.9. Fixed by 1 Microsoft security update.
All about CVE-2026-42833: the Senserva AI read, whether it is exploited, the official patches, its change history, and the questions admins ask.
CVE-2026-42833 is a critical severity Microsoft vulnerability with a CVSS score of 9.9. Microsoft has shipped the fix: deploy the update below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Risk summary
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Senserva AI Opinion for CVE-2026-42833
The second Critical Severity (CVSS 9.9) Remote Code Execution flaw disclosed against Microsoft Dynamics 365 on-premises version 9.1 in this period, which suggests researchers are actively working over that product's attack surface. EPSS is 1% and there is no KEV entry, but two top-rated RCEs in the same on-prem business platform is a trend worth respecting. Dynamics servers hold customer and financial data and often sit outside routine patch automation.
Do this: Bundle this with CVE-2026-42898 into a single Dynamics 365 on-premises maintenance window and verify the servers are shielded from direct internet access.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2026-42833
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2026-42833
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
Exploitation and severity
Not in the CISA KEV catalog. EPSS exploit probability 1.2%. CVSS 9.9 (Critical).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
Official patch(es) for CVE-2026-42833
Elevated priority: high severity or a meaningful exploitation probability, sooner if an affected product is internet-facing. In Intune or Defender, confirm whether the fixing update KB5078943 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.
Apply the Microsoft security update below to fix CVE-2026-42833. Each KB page carries the Microsoft Update Catalog download, Microsoft's known issues for the update, a copy-paste PowerShell check for whether it is installed, and the Senserva AI read.
Affected products
Common questions about CVE-2026-42833
Is CVE-2026-42833 actively exploited?
It is not currently listed in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score puts the probability of exploitation in the next 30 days at 1.2%.
What patch fixes CVE-2026-42833?
Microsoft fixed CVE-2026-42833 in KB5078943. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2026-42833?
Microsoft Dynamics 365 (on-premises) version 9.0, Microsoft Dynamics 365 (on-premises) version 9.1.
Can I ask my own AI about CVE-2026-42833?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2026-42833's key facts: severity, CVSS, EPSS exploit probability, CISA KEV status, and the fixing KB. Copy it into Claude, ChatGPT, or Copilot for a triage plan; the data is refreshed three times a day (5 AM, 12:30 PM, and 7 PM US Central).
Fixed by the same update
If you are patching CVE-2026-42833, the same update also fixes these:
Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.
