# CVE-2022-49820: mctp i2c: don't count unused / invalid keys for flow release

> A logic error in the Linux kernel MCTP I2C driver can trigger a warning and potential instability when releasing unused flows, requiring a kernel patch.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **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:** 1 May 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-49820, GHSA-whp8-mg46-9399, UBUNTU-CVE-2022-49820

## What is CVE-2022-49820?

CVE-2022-49820 is a medium-severity denial of service vulnerability in Linux kernel, published on 1 May 2025. 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:

mctp i2c: don't count unused / invalid keys for flow release

We're currently hitting the WARN_ON in mctp_i2c_flow_release:

    if (midev->release_count > midev->i2c_lock_count) {
        WARN_ONCE(1, "release count overflow");

This may be hit if we expire a flow before sending the first packet it
contains - as we will not be pairing the increment of release_count
(performed on flow release) with the i2c lock operation (only
performed on actual TX).

To fix this, only release a flow if we've encountered it previously (ie,
dev_flow_state does not indicate NEW), as we will mark the flow as
ACTIVE at the same time as accounting for the i2c lock operation. We
also need to add an INVALID flow state, to indicate when we've done the
release.

## Which versions are affected by CVE-2022-49820?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49820?

Apply the vendor's patch.

## Is CVE-2022-49820 being exploited?

There is no known exploitation of CVE-2022-49820 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-49820 and fix it if it is affected.

What it is: CVE-2022-49820 is a medium-severity denial of service vulnerability in Linux kernel, published on 1 May 2025. 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-2022-49820 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2022-49820/ (Markdown: https://insights.sbomify.com/CVE-2022-49820/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49820
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49820
- OSV: https://osv.dev/vulnerability/CVE-2022-49820

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49820/
Summaries are generated and may contain mistakes; the official description above is the record.