External risk intelligence

Oracle REST Data Services Compromise Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.9)

CVE-2026-46839

Oracle REST Data Services acts as a bridge between web browsers and Oracle databases. It is commonly deployed as an internet-facing API or web service to facilitate data access, making it a standard component for public-facing application connectivity.

Oracle Rest Data Services

24.2.0 to 26.1.0

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability has been identified in Oracle REST Data Services, a component that bridges web browsers and Oracle databases, often used for public-facing application connectivity. This issue, if exploited by a low-privileged attacker, could lead to a full takeover of the service and potentially impact other connected products due to its network accessibility via HTTPS.

Attackers can take over Oracle's data services.
It affects systems that connect applications to databases.
Confirming relevance and exposure is the key action.

Attack Path

How an attacker could exploit the issue

An attacker with low privileges can exploit this vulnerability by accessing Oracle REST Data Services over a network. The vulnerability in the Core component of Oracle REST Data Services can lead to a complete takeover of the service, potentially impacting other connected products.

Network access required.
Vulnerable component: Core.
Risk: Service takeover.

Live Threat

Current exploitation, exposure, and threat context

A low-privileged attacker with network access could compromise Oracle REST Data Services, potentially impacting other products. This vulnerability could allow for a complete takeover of the Oracle REST Data Services, affecting confidentiality, integrity, and availability.

Oracle REST Data Services
Network access via HTTPS
Takeover of service

Operational Fix

Recommended remediation, mitigation, and detection steps

Real-world action for this vulnerability likely falls to teams managing Oracle applications and their underlying infrastructure. The first practical step is to identify all instances of Oracle REST Data Services, determine their network accessibility and business criticality, and then locate the accountable owners. This information is crucial for prioritizing remediation efforts and planning subsequent actions, which may involve vendor coordination or temporary risk reduction measures.

Identify affected Oracle REST Data Services instances.
Verify network reachability and business criticality.
Plan targeted remediation based on ownership and risk.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is Oracle REST Data Services and what is it used for?

Oracle REST Data Services (ORDS) acts as a bridge between web browsers and Oracle databases. It is commonly used to enable public-facing applications to connect to and interact with Oracle databases by providing web service APIs.

What type of vulnerability is CVE-2026-46839 in Oracle REST Data Services?

CVE-2026-46839 is a critical vulnerability classified as CWE-284 (Improper Access Control). It allows a low-privileged attacker with network access to compromise the Oracle REST Data Services.

What are the conditions for an attacker to exploit this CVE?

An attacker needs network access via HTTPS to exploit this vulnerability. Crucially, the attacker only requires low privileges, and no user interaction is needed for exploitation. The vulnerability is not triggered if the attacker lacks network access or sufficient privileges.

Who should be concerned about this vulnerability, considering its exposure?

Organizations running Oracle REST Data Services that are accessible from the internet should be concerned. Halo classifies this as an external threat because it can be exploited over the network, potentially impacting public-facing applications and services.

What is the first step for teams running Oracle REST Data Services?

The initial step is to identify all instances of Oracle REST Data Services within your environment. You should then determine their network accessibility and their importance to business operations to plan for remediation.

References

www.oracle.com/security-alerts/cspumay2026.html

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.