Affects Oracle Database Net Services — widely deployed enterprise infrastructure; unauthenticated remote compromise or DoS can disrupt organizations.
CVE-2026-47040
Unauthenticated remote vulnerability in Oracle Net Services enabling data access or DoS.
Is CVE-2026-47040 being exploited?
Not confirmed. CVE-2026-47040 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 0.47% probability of exploitation in the next 30 days.
How severe is CVE-2026-47040?
CVE-2026-47040 is rated Critical with a CVSS score of 9.1. 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-2026-47040?
Yes. A fix has been recorded for CVE-2026-47040. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-47040 affect?
CVE-2026-47040 affects Oracle Net Services (Oracle Database), Oracle Database 19.3 - 19.31, Oracle Database 21.3 - 21.22, Oracle Database 23.4.0 - 23.26.2. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-47040?
Apply vendor patch when available; block Oracle Net (TCP 1521) from untrusted networks and monitor logs
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated remote attacker via Oracle Net can access sensitive data or cause service hang/crash (DoS).
Immediate action required
- affected>= 19.3 and <= 19.31
- affected>= 21.3 and <= 21.22
- affected>= 23.4.0 and <= 23.26.2
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.