---
id: "CVE-2026-91254"
kind: "vulnerability"
aliases: ["CVE-2026-91254"]
title: "Oracle Solaris 11.4 kernel flaw lets unauthenticated network attacker crash the host"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["infrastructure", "kernel", "oracle", "self-hosted", "solaris"]
not_affected_if: ["no-solaris-11.4"]
published_at: "2026-10-20T22:20:26+00:00"
first_seen_at: "2026-10-23T21:57:26+00:00"
updated_at: "2026-10-25T03:18:38+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91254", "first_seen_at": "2026-10-23T21:57:26+00:00"}]
---

# Oracle Solaris 11.4 kernel flaw lets unauthenticated network attacker crash the host

A flaw in the Oracle Solaris 11.4 kernel can be triggered over HTTP by an unauthenticated attacker, causing a hang or repeatable crash. The sources describe only a denial of service, not code execution or data theft.

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

## How to check

- Run `uname -v` on each Solaris host to see the installed release and compare it with Oracle's patch advisory
- unknown for other checks; the sources do not name the affected HTTP-facing service or configuration

## Fix

- Apply the Oracle Solaris 11.4 kernel patch from Oracle's Critical Patch Update for the release in use
- unknown for a specific fixed version; the sources do not give one

## Timeline

- 2026-10-23T21:57:26+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91254

## From the sources

Vulnerability in the Oracle Solaris product of Oracle Systems (component: Kernel).   The supported version that is affected is 11.4. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Oracle Solaris.  Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Oracle Solaris. 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).

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_