# CVE-2026-81936 — Lenovo XClarity Controller

> As of 2026-11-14, CVE-2026-81936 is a MEDIUM-severity vulnerability in Lenovo XClarity Controller, CVSS v3.1 6.8, EPSS 0.3% (28.6th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-81936, most recently “Lenovo ThinkSystem V4 XCC3 Firmware Restores Default OpenBMC Root Credentials After Reset to Default (CVE-2026-81936)”.

**Last updated:** 2026-11-14

## What is CVE-2026-81936?

An internal security review identified a development regression from ThinkSystem v4 XClarity Controller 3 (XCC3) versions (2.51) IHX432Y to (2.56) IHX436K which re-introduces the default OpenBMC root password upon performing an XCC Reset to Default operation. An attacker can gain access to enabled administrative interfaces of XCC using the default OpenBMC credential re-introduced after Reset to Default. Additionally, this provides access to the underlying XCC Operating System which is not normally accessible. Only these versions are affected and are no longer available for download. Process enhancements have also been made to prevent and identify potential future regression.

The record classifies CVE-2026-81936 under weakness class [CWE-1392](https://intel.threadlinqs.com/cwe/CWE-1392). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs high-privilege credentials, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 4 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 6.8 — MEDIUM (`CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H`)
- **CVSS v4.0 base score:** 7.1 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 28.6% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 4.5/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-11-11

## Is CVE-2026-81936 being exploited?

It currently carries a trending score of 5 in the Threadlinqs vulnerability feed.

## Affected products and versions

- **Lenovo**: XClarity Controller

## How to fix CVE-2026-81936

No vendor patch reference has been recorded for CVE-2026-81936 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-81936

1 tracked threat in the Threadlinqs corpus references CVE-2026-81936, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Lenovo ThinkSystem V4 XCC3 Firmware Restores Default OpenBMC Root Credentials After Reset to Default (CVE-2026-81936)](https://intel.threadlinqs.com/threat/TL-2026-6059) — HIGH · 2026-11-14

## Sources

Enriched from CVE.org, NVD, FIRST EPSS. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [lenovopress.lenovo.com](https://lenovopress.lenovo.com/lp2273-lenovo-xclarity-controller-3-xcc3)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-81936
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