CVE-2026-91503 Oracle Corporation CVE debrief

Who should care

Defenders responsible for Oracle Database Server deployments, especially those with low-privileged users having network access, should assess exposure and prioritize patching or mitigation.

Why it matters

Defenders should care about CVE-2026-91503 because it allows low-privileged attackers to compromise VPD and access critical data in Oracle Database Server deployments. Affected versions require patching or mitigation to prevent exploitation.

• Potential unauthorized data modifications
• Potential unauthorized data access
• Need for patching or mitigation to prevent exploitation
• Verification of affected versions and exposure

Technical summary

The vulnerability in the VPD component of Oracle Database Server allows a low-privileged attacker with Create Table privilege and network access via Oracle Net to compromise VPD. Successful attacks can result in unauthorized creation, deletion, or modification access to critical data or all VPD accessible data, as well as unauthorized access to critical data or complete access to all VPD accessible data.

Defensive priority

Defenders should prioritize patching or mitigating this vulnerability, especially in environments where low-privileged users have network access to the Oracle Database Server.

Recommended defensive actions

• Patch or upgrade to a non-affected version of Oracle Database Server
• Restrict network access to the Oracle Database Server
• Monitor for suspicious activity related to VPD
• Verify affected versions and exposure in managed environments
• Review compensating controls for exposed systems while remediation is scheduled
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD detail page provide information on the vulnerability, its impacts, and affected versions. Defenders should verify the affected versions of Oracle Database Server in their environments and assess exposure. The vulnerability allows low-privileged attackers to compromise VPD and access critical data. Evidence is limited to public sources, and defenders should exercise caution when verifying exposure. Additional verification tasks include reviewing Oracle's official advisory and assessing network access controls.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.