CVE-2026-83276
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk27th percentile - higher than 27% of all known CVEs
Summary
Vulnerability in Oracle Fusion Middleware Helidon product (helidon-webclient-http2 component) affects versions 4.0.0-4.5.4. An unauthenticated attacker with network access via HTTP/2 can cause a hang or frequently repeatable crash (complete DOS). The vulnerability is easily exploitable.
Risk Assessment
An attacker can cause complete denial of service, preventing use of Helidon-based applications. This may disrupt availability of critical services.
Recommendation
Urgently apply Oracle patches for Helidon versions 4.0.0-4.5.4. Additionally, consider restricting network access to the Helidon server.
Other vulnerabilities in Helidon
See all- CVE-2026-73930Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) affects versions 3.0.0-3.2.19 and 4.0.0-4.5.2. Easily exploitable flaw allows unauthenticated attacker with network access via HTTP to perform unauthorized creation, deletion, or modification of data, unauthorized read access to a subset of data, and cause partial denial of service. Attacks may impact additional products (scope change). CVSS score 9.9.
- CVE-2026-73924Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server) versions 1.0.0-1.4.18. Allows unauthenticated attacker via HTTP to perform unauthorized creation, deletion, or modification of data and access data. CVSS 9.1.
- CVE-2026-73922Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server) versions 1.0.0-1.4.18. Allows unauthenticated attacker via HTTP to perform unauthorized creation, deletion, or modification of data and access data. CVSS 9.1.
- CVE-2026-73921Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) affects versions 1.0.0-1.4.19. Easily exploitable flaw allows unauthenticated attacker with network access via HTTP to take over Helidon. CVSS score 9.8.
- CVE-2026-73920Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server) versions 4.0.0-4.4.1. Allows unauthenticated attacker via HTTP to perform unauthorized creation, deletion, or modification of data, access data, and cause partial denial of service. CVSS 9.4.
- CVE-2026-73917Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) affects versions 4.0.0-4.4.1. Easily exploitable flaw allows unauthenticated attacker with network access via HTTP to perform unauthorized creation, deletion, or modification of data and unauthorized access to data. CVSS score 9.1.
- CVE-2026-73916Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) affects versions 3.0.0-3.2.17. Easily exploitable flaw allows unauthenticated attacker with network access via HTTP to perform unauthorized creation, deletion, or modification of data and unauthorized access to data. CVSS score 9.1.
- CVE-2026-73912Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) affects versions 4.0.0-4.4.1. Easily exploitable flaw allows unauthenticated attacker with network access via HTTP to take over Helidon. CVSS score 9.8.
- CVE-2026-73905Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) versions 4.0.0-4.4.1. Easily exploitable by unauthenticated attacker with network access via HTTP, allowing takeover of Helidon. CVSS 9.8 (high impact on confidentiality, integrity, and availability).
- CVE-2026-73866Critical
Vulnerability in Oracle Fusion Middleware Helidon (Imperative Web Server component) affects versions 4.0.0-4.4.1. Easily exploitable flaw allows unauthenticated attacker with network access via HTTP to perform unauthorized creation, deletion, or modification of data and unauthorized access to data. CVSS score 9.1.
Original NVD description (English source)
Vulnerability in the Helidon product of Oracle Fusion Middleware (component: helidon-webclient-http2). Supported versions that are affected are 4.0.0-4.5.4. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP/2 to compromise Helidon. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Helidon. CVSS 3.1 Base Score 7.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
Vulnerability data from NVD (NIST) · CISA KEV · EPSS