CVE-2026-83416: 
Oracle Coherence vulnerability analysis and mitigation

CVE-2026-83416 is a partial denial-of-service vulnerability in the Core component of Oracle Coherence, part of Oracle Fusion Middleware. It affects supported versions 12.2.1.4.0, 14.1.1.0.0, 14.1.2.0.0, and 15.1.1.0.0. The vulnerability was disclosed and patched on September 15, 2026, as part of Oracle's Critical Security Patch Update (CSPU) for that month. It carries a CVSS v3.1 base score of 4.3 (Medium) (Oracle Advisory).

The vulnerability resides in the Core component of Oracle Coherence and is classified as an availability-impacting flaw (CWE category: Availability). A low-privileged attacker with network access via HTTP can exploit this vulnerability without requiring user interaction, making it "easily exploitable" per Oracle's classification. The attack vector is network-based over HTTP (and by extension HTTPS), with low attack complexity and no user interaction required. No public technical write-ups or proof-of-concept code have been identified at this time (Oracle Advisory).

Successful exploitation results in a partial denial of service of Oracle Coherence, degrading but not fully disabling the service's availability. There is no impact on confidentiality or integrity — the vulnerability is limited strictly to availability. Given Oracle Coherence's role as an in-memory data grid used in enterprise middleware environments, partial service disruption could affect dependent applications and workflows (Oracle Advisory).

There is no public proof-of-concept exploit and no evidence of active in-the-wild exploitation as of the time of disclosure. The EPSS score is approximately 0.0036 (0.36%), indicating a low probability of exploitation in the near term. The vulnerability is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog. Detection coverage is available via Qualys (detection ID 388781) and Tenable (Nessus plugin 346314) (Oracle Advisory).

Oracle has released a patch for CVE-2026-83416 as part of the September 2026 Critical Security Patch Update, applicable to all four affected versions (12.2.1.4.0, 14.1.1.0.0, 14.1.2.0.0, and 15.1.1.0.0). Oracle strongly recommends applying the patch as soon as possible. As a temporary workaround, organizations can restrict network access to Oracle Coherence HTTP endpoints to trusted, low-privileged accounts only, and implement network segmentation to limit exposure. Oracle cautions that workarounds may break application functionality and should not be considered long-term solutions (Oracle Advisory).