---
id: "CVE-2026-91461"
kind: "vulnerability"
aliases: ["CVE-2026-91461"]
title: "Oracle Java SE JSSE: TLS flaw lets unauthenticated network attacker modify some data"
severity: "low"
cvss: 3.7
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["graalvm", "java", "oracle-jdk", "runtime", "web-services"]
not_affected_if: ["default-config"]
published_at: "2026-10-20T22:20:49+00:00"
first_seen_at: "2026-10-23T21:57:27+00:00"
updated_at: "2026-10-25T04:43:43+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91461", "first_seen_at": "2026-10-23T21:57:27+00:00"}]
---

# Oracle Java SE JSSE: TLS flaw lets unauthenticated network attacker modify some data

A flaw in the JSSE component of Oracle Java SE and Oracle GraalVM lets an unauthenticated attacker over TLS write some accessible data. The attack is hard to carry out and works by supplying data to Java APIs, such as through a web service.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `java -version` and compare against the affected releases: Java SE 8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27; GraalVM for JDK 17.0.20.1 and 21.0.12.1; GraalVM Enterprise 21.3.19.1.1.

## Fix

- Move Oracle Java SE to a patched release from Oracle's April 2026 Critical Patch Update, such as `21.0.12.1` or `25.0.4.1`, per the vendor advisory.
- Move Oracle GraalVM for JDK to a patched build from the same update.
- Oracle's advisory for this CVE was not in the sources, so the exact fixed build per line is unknown.

## Timeline

- 2026-10-23T21:57:27+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91461

## From the sources

Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: JSSE).  Supported versions that are affected are Oracle Java SE: 8u503, 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27; Oracle GraalVM for JDK: 17.0.20.1 and  21.0.12.1; Oracle GraalVM Enterprise Edition: 21.3.19.1.1. Difficult to exploit vulnerability allows unauthenticated attacker with network access via TLS to compromise Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition.  Successful attacks of this vulnerability can result in  unauthorized update, insert or delete access to some of Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition accessible data. Note: This vulnerability can only be exploited by supplying data to APIs in the specified Component without using Untrusted Java Web Start applications or Untrusted Java applets, such as through a web service. CVSS 3.1 Base Score 3.7 (Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N).

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