# CVE-2026-72040: ipmi: fix refcount leak in i_ipmi_request()

> A refcount leak in the Linux kernel IPMI driver allows local attackers to cause memory exhaustion and denial of service.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Aug 2026
- **Updated:** 23 Aug 2026
- **Also known as:** BELL-CVE-2026-72040, DEBIAN-CVE-2026-72040, GHSA-j63g-h4gq-q67f, UBUNTU-CVE-2026-72040

## What is CVE-2026-72040?

CVE-2026-72040 is a memory corruption vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

ipmi: fix refcount leak in i_ipmi_request()

When a caller provides a `supplied_recv` message to i_ipmi_request(),
the function increments the user's `nr_msgs` reference count. If an
error occurs later, the out_err cleanup path only frees the recv_msg
if the function allocated it itself (i.e., !supplied_recv). In the
supplied_recv case the cleanup is skipped, leaving the reference count
elevated. The caller ipmi_request_supply_msgs() does not release the
supplied_recv on error, so the reference is permanently leaked.

Fix this by explicitly reverting the reference count operations when a
supplied recv_msg with a valid user pointer is present in the error
path: decrement nr_msgs and drop the user's kref.

## Which versions are affected by CVE-2026-72040?


## How do I fix CVE-2026-72040?

Apply the vendor's patch.

## Is CVE-2026-72040 being exploited?

There is no known exploitation of CVE-2026-72040 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72040 and fix it if it is affected.

What it is: CVE-2026-72040 is a memory corruption vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-72040 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-72040/ (Markdown: https://insights.sbomify.com/CVE-2026-72040/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72040
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72040
- OSV: https://osv.dev/vulnerability/CVE-2026-72040

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72040/
Summaries are generated and may contain mistakes; the official description above is the record.