Affects VMware vCenter, a widely deployed enterprise management platform; auth bypass can yield full control of virtualization infrastructure and disrupt operations.
CVE-2026-59309
VMware vCenter auth bypass lets network attackers access vCenter without credentials.
Is CVE-2026-59309 being exploited?
Not confirmed. CVE-2026-59309 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 7.9% probability of exploitation in the next 30 days.
How severe is CVE-2026-59309?
CVE-2026-59309 is rated Critical with a CVSS score of 9.8. 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-2026-59309?
Yes. A fix has been recorded for CVE-2026-59309. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-59309 affect?
CVE-2026-59309 affects VMware vCenter Server (VMware Directory Service). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-59309?
Isolate vCenter, restrict management network access, enable logging/monitoring, apply vendor patch when released.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote authentication bypass allows an attacker with network access to gain unauthorized/admin-level vCenter access, control VMs, exfiltrate data, and move laterally.
Immediate action required
- affected9.1.x.x
- affected9.0.x.x
- affected5.x
- affected3.0
- affected5.1.x
- affected5.0.x
- affected4.x
- affected3.0
- affected>= 9.1.x.x and < 9.1.0.0300
- affected>= 9.0.x.x and < 9.0.2.0100
- affected>= 8.0 and < 8.0 U3k
- affected9.1.x.x
- affected9.0.x.x
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.