# CVE-2026-53082: net: hamradio: 6pack: fix uninit-value in sixpack_receive_buf

> An attacker can read uninitialized kernel memory via the hamradio 6pack driver due to improper handling of TTY error flags.

- **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:** 24 Jun 2026
- **Updated:** 24 Jun 2026
- **Also known as:** BELL-CVE-2026-53082, DEBIAN-CVE-2026-53082, GHSA-33fq-h3x2-m8v9, ROOT-OS-DEBIAN-11-CVE-2026-53082, ROOT-OS-DEBIAN-12-CVE-2026-53082, ROOT-OS-UBUNTU-2204-CVE-2026-53082, ROOT-OS-UBUNTU-2404-CVE-2026-53082, UBUNTU-CVE-2026-53082

## What is CVE-2026-53082?

CVE-2026-53082 is a medium-severity vulnerability in Linux kernel, published on 24 Jun 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:

net: hamradio: 6pack: fix uninit-value in sixpack_receive_buf

sixpack_receive_buf() does not properly skip bytes with TTY error flags.
The while loop iterates through the flags buffer but never advances the
data pointer (cp), and passes the original count (including error bytes)
to sixpack_decode(). This causes sixpack_decode() to process bytes that
should have been skipped due to TTY errors.  The TTY layer does not
guarantee that cp[i] holds a meaningful value when fp[i] is set, so
passing those positions to sixpack_decode() results in KMSAN reporting
an uninit-value read.

Fix this by processing bytes one at a time, advancing cp on each
iteration, and only passing valid (non-error) bytes to sixpack_decode().
This matches the pattern used by slip_receive_buf() and
mkiss_receive_buf() for the same purpose.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2026-53082?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53082?

Apply the vendor's patch.

## Is CVE-2026-53082 being exploited?

There is no known exploitation of CVE-2026-53082 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-2026-53082 and fix it if it is affected.

What it is: CVE-2026-53082 is a medium-severity vulnerability in Linux kernel, published on 24 Jun 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-2026-53082 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-2026-53082/ (Markdown: https://insights.sbomify.com/CVE-2026-53082/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53082
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53082
- OSV: https://osv.dev/vulnerability/CVE-2026-53082

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53082/
Summaries are generated and may contain mistakes; the official description above is the record.