What is the CVSS score of CVE-2026-73877?

CVE-2026-73877 has a CVSS 3.1 base score of 5.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N. EPSS exploitation probability: 0.3%.

Oracle Helidon CVE-2026-73877

EUVD-2026-62121 MEDIUM

Improper Access Control (CWE-284)

2026-08-18 secalert_us@oracle.com

GHSA-mw3j-qwv8-jvwv

Authentication Bypass Oracle Helidon

5.3

CVSS 3.1 · Vendor: oracle

Severity by source

Vendor (oracle) PRIMARY

5.3 MEDIUM

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

vuln.today AI

5.3 MEDIUM

Network-reachable HTTP service, no credentials required per auth-bypass nature, partial read only - no integrity or availability impact applies.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (oracle).

CVSS VectorVendor: oracle

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Lifecycle Timeline

Analysis Generated

Aug 19, 2026 - 02:49 vuln.today

DescriptionCVE.org

Vulnerability in the Helidon product of Oracle Fusion Middleware (component: Imperative Web Server). The supported version that is affected is 3.2.18. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Helidon. Successful attacks of this vulnerability can result in unauthorized read access to a subset of Helidon accessible data. CVSS 3.1 Base Score 5.3 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).

AnalysisAI

Authentication bypass in Helidon 3.2.18's Imperative Web Server component allows unauthenticated remote attackers to read a subset of data accessible within the Helidon service over HTTP. The CVSS vector (AV:N/AC:L/PR:N/UI:N) confirms this is trivially exploitable from any network location against default deployments without credentials. …

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Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata

Access

Identify exposed Helidon 3.2.18 service

Delivery

Send crafted HTTP request

Exploit

Bypass Imperative Web Server auth check

Execution

Access protected endpoint

Impact

Exfiltrate subset of application data

Access

Identify exposed Helidon 3.2.18 service

Delivery

Send crafted HTTP request

Exploit

Bypass Imperative Web Server auth check

Execution

Access protected endpoint

Impact

Exfiltrate subset of application data

Vulnerability AssessmentAI

Exploitation	Exploitation requires network-level HTTP access to an instance of Helidon 3.2.18 running the Imperative Web Server component. … Additional conditions and limiting factors are described in the full assessment.
Risk Assessment	CVSS 3.1 base score of 5.3 (Medium) reflects real-world risk reasonably well for this vulnerability. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in.
Exploit Scenario	An attacker with HTTP network access to a Helidon 3.2.18 Imperative Web Server sends a crafted HTTP request that bypasses the service's access-control checks - potentially by manipulating a path, header, or method that the security filter does not evaluate - and receives a response containing data from a protected endpoint. No authentication credentials are required, making this exploitable via automated scanning tools or a simple curl invocation. …
Remediation	Apply Oracle's August 2026 Critical Security Patch Update (CSPU), referenced at https://www.oracle.com/security-alerts/cspuaug2026.html. … Detailed patch versions, workarounds, and compensating controls in full report.