# CVE-2026-68192: wifi: brcmfmac: make release_scratchbuffers idempotent

> A double-free vulnerability in the brcmfmac Wi-Fi driver allows attackers to cause denial of service or potentially execute code via repeated teardown operations.

- **Severity:** High 8.8 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-68192, DEBIAN-CVE-2026-68192, GHSA-52hv-vfrj-x3fv, UBUNTU-CVE-2026-68192

## What is CVE-2026-68192?

CVE-2026-68192 is a high-severity use after free vulnerability in Linux, published on 10 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:

wifi: brcmfmac: make release_scratchbuffers idempotent

brcmf_pcie_release_scratchbuffers() frees the shared.scratch and
shared.ringupd DMA buffers with dma_free_coherent() but does not clear
the pointers afterwards, unlike the sibling release_ringbuffers() which
NULLs commonrings/flowrings/idxbuf on release.

Both the bus_reset .reset callback (brcmf_pcie_reset) and
brcmf_pcie_remove() call release_scratchbuffers.  When reset teardown
has run before removal, remove's own teardown would call
dma_free_coherent() a second time on the already-freed DMA allocation.

NULL the pointers after free, matching release_ringbuffers(), so a later
release observes that the allocation has already been released.  This
patch makes repeated sequential release safe; the reset-work lifetime is
handled separately by the following patch.

This issue was found by an in-house static analysis tool.

Weakness: CWE-415 (Double Free)

## Which versions are affected by CVE-2026-68192?


## How do I fix CVE-2026-68192?

Apply the vendor's patch.

## Is CVE-2026-68192 being exploited?

There is no known exploitation of CVE-2026-68192 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68192 and fix it if it is affected.

What it is: CVE-2026-68192 is a high-severity use after free vulnerability in Linux, published on 10 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-2026-68192 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-2026-68192/ (Markdown: https://insights.sbomify.com/CVE-2026-68192/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68192
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68192
- OSV: https://osv.dev/vulnerability/CVE-2026-68192

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68192/
Summaries are generated and may contain mistakes; the official description above is the record.