Oracle Java - CVE-2026-91403 - Score: 9.1
Description
CVE-2026-91403 is a high-severity security vulnerability in Oracle Java SE and Oracle GraalVM products affecting the JSSE component. It is remotely exploitable over a network without authentication and can impact confidentiality and integrity. The vulnerability affects multiple supported versions of Oracle Java SE and GraalVM. Oracle has released security patches for supported versions and recommends upgrading to supported versions to receive these patches.
Reddit Discussion
Affected software
pkg:maven/com.oracle.java/sepkg:maven/com.oracle.graalvm/graalvmRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-91403 is a remotely exploitable vulnerability in the JSSE component of Oracle Java SE, Oracle GraalVM for JDK, and Oracle GraalVM Enterprise Edition. It can be exploited without authentication over a network, potentially impacting confidentiality and integrity. The vulnerability can be triggered via APIs in the JSSE component, such as through web services supplying data to these APIs. It also affects Java deployments running sandboxed Java Web Start applications or sandboxed Java applets that load and run untrusted code relying on the Java sandbox for security. Oracle has released patches for multiple versions including Java SE 8u511, 11.0.33, 17.0.21, 21.0.13, 25.0.5, 27.0.1 and GraalVM versions 17.0.21, 21.0.13, and 21.3.20.
Potential Impact
Successful exploitation of this vulnerability can lead to high impact on confidentiality and integrity of affected systems. The vulnerability is remotely exploitable without authentication, increasing the risk of attack. Availability is not impacted. The vulnerability affects multiple widely used Oracle Java SE and GraalVM versions, potentially exposing many deployments.
Mitigation Recommendations
Oracle has released official security patches for supported versions of Oracle Java SE and GraalVM to address CVE-2026-91403. Customers should apply these patches promptly. Oracle recommends upgrading to supported product versions to ensure availability of security updates. For versions not under Premier or Extended Support, Oracle does not provide patches and recommends upgrading to supported versions. No other mitigation or workaround is specified by Oracle.
Technical Details
- Source Type
- Subreddit
- cybersecurity
- Reddit Score
- 0
- Discussion Level
- minimal
- Content Source
- reddit_link_post
- Post Type
- link
- Newsworthiness Assessment
- {"score":45,"reasons":["external_link","newsworthy_keywords:cve-","security_identifier","established_author","very_recent"],"isNewsworthy":true,"foundNewsworthy":["cve-"]}
- Has External Source
- true
- Trusted Domain
- false
Threat ID: 6ad9fe544d27ba8daa516d8b
Added to database: 10/22/2026, 12:15:16 UTC
Last enriched: 10/22/2026, 12:15:21 UTC
Last updated: 10/22/2026, 16:45:24 UTC
Views: 192
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