Cyber Posture

CVE-2026-21997

High

Published: 21 April 2026

Published
21 April 2026
Modified
01 May 2026
KEV Added
Patch
CVSS Score 8.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N
EPSS Score 0.0002 6.6th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-21997 is a high-severity Improper Access Control (CWE-284) vulnerability in Oracle Life Sciences Empirica Signal. Its CVSS base score is 8.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 6.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Timely identification, reporting, and correction of the improper access control flaw (CWE-284) in the Common Core component directly prevents exploitation by low-privileged attackers.

prevent

Enforcing approved authorizations for logical access to information and system resources directly mitigates the improper access control vulnerability allowing unauthorized data creation, deletion, modification, and read access.

prevent

Applying least privilege restricts low-privileged attackers from performing high-impact actions like modifying critical data even if access controls are bypassed.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

Remote network-accessible improper access control flaw in a web-exposed Oracle application directly enables exploitation via T1190.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Vulnerability in the Oracle Life Sciences Empirica Signal product of Oracle Life Science Applications (component: Common Core). Supported versions that are affected are 9.2.1-9.2.3. Easily exploitable vulnerability allows low privileged attacker with network access via HTTP to compromise Oracle Life…

more

Sciences Empirica Signal. While the vulnerability is in Oracle Life Sciences Empirica Signal, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized creation, deletion or modification access to critical data or all Oracle Life Sciences Empirica Signal accessible data as well as unauthorized read access to a subset of Oracle Life Sciences Empirica Signal accessible data. CVSS 3.1 Base Score 8.5 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N).

Deeper analysisAI

CVE-2026-21997 is a vulnerability in the Common Core component of the Oracle Life Sciences Empirica Signal product within Oracle Life Science Applications. Supported versions affected by this issue are 9.2.1 through 9.2.3. The vulnerability, associated with CWE-284 (Improper Access Control), carries a CVSS 3.1 Base Score of 8.5, with the vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:N, indicating high confidentiality and integrity impacts but no availability impact.

A low-privileged attacker with network access via HTTP can easily exploit this vulnerability to compromise Oracle Life Sciences Empirica Signal. While the flaw resides in Empirica Signal, exploitation enables a scope change that may significantly impact additional products. Successful attacks allow unauthorized creation, deletion, or modification of critical data or all accessible data in Empirica Signal, as well as unauthorized read access to a subset of that data.

Oracle's Critical Patch Update advisory at https://www.oracle.com/security-alerts/cpuapr2026.html details patches and recommended mitigations for this vulnerability.

Details

CWE(s)

Affected Products

oracle
life sciences empirica signal
9.2.1 — 9.2.3

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References