Authenticated remote code execution in Windows SMB Server affects widely deployed Microsoft SMB service; potential for system compromise and lateral movement across enterprises.
CVE-2026-62790
Authenticated RCE in Windows SMB Server via heap overflow.
Is CVE-2026-62790 being exploited?
Not confirmed. CVE-2026-62790 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.66% probability of exploitation in the next 30 days.
How severe is CVE-2026-62790?
CVE-2026-62790 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-62790?
Yes. A fix has been recorded for CVE-2026-62790. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-62790 affect?
CVE-2026-62790 affects Microsoft Windows SMB Server, Windows Server SMB service (multiple versions). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-62790?
Apply vendor patch when released; block SMB from untrusted networks and enforce network segmentation.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Authenticated remote code execution via SMB heap buffer overflow; allows full system compromise and lateral movement.
Immediate action required
- affected>= 10.0.14393.0 and < 10.0.14393.9418
- affected>= 10.0.17763.0 and < 10.0.17763.9121
- affected>= 10.0.19044.0 and < 10.0.19044.7663
- affected>= 10.0.19045.0 and < 10.0.19045.7663
- affected>= 10.0.22631.0 and < 10.0.22631.7517
- affected>= 10.0.22631.0 and < 10.0.22631.7517
- affected>= 10.0.26100.0 and < 10.0.26100.9168
- affected>= 10.0.26200.0 and < 10.0.26200.9168
- affected>= 10.0.28000.0 and < 10.0.28000.2704
- affected>= 6.2.9200.0 and < 6.2.9200.26280
- affected>= 6.3.9600.0 and < 6.3.9600.23338
- affected>= 6.3.9600.0 and < 6.3.9600.23338
- affected>= 6.2.9200.0 and < 6.2.9200.26280
- affected>= 10.0.14393.0 and < 10.0.14393.9418
- affected>= 10.0.14393.0 and < 10.0.14393.9418
- affected>= 10.0.17763.0 and < 10.0.17763.9121
- affected>= 10.0.17763.0 and < 10.0.17763.9121
- affected>= 10.0.20348.0 and < 10.0.20348.5499
- affected>= 10.0.26100.0 and < 10.0.26100.33296
- affected>= 10.0.26100.0 and < 10.0.26100.33296
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.