# CVE-2025-68362: wifi: rtl818x: rtl8187: Fix potential buffer underflow in rtl8187_rx_cb()

> A buffer underflow in the rtl8187 WiFi driver allows attackers to cause a kernel panic via truncated packets, requiring a patch.

- **Severity:** Not scored
- **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:** 24 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** AZL-73063, BELL-CVE-2025-68362, DEBIAN-CVE-2025-68362, GHSA-x793-gh9g-39hm, ROOT-OS-DEBIAN-11-CVE-2025-68362, ROOT-OS-DEBIAN-12-CVE-2025-68362, ROOT-OS-DEBIAN-13-CVE-2025-68362, ROOT-OS-UBUNTU-2204-CVE-2025-68362, ROOT-OS-UBUNTU-2404-CVE-2025-68362, UBUNTU-CVE-2025-68362

## What is CVE-2025-68362?

CVE-2025-68362 is a memory corruption vulnerability in Linux, published on 24 Dec 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:

wifi: rtl818x: rtl8187: Fix potential buffer underflow in rtl8187_rx_cb()

The rtl8187_rx_cb() calculates the rx descriptor header address
by subtracting its size from the skb tail pointer.
However, it does not validate if the received packet
(skb->len from urb->actual_length) is large enough to contain this
header.

If a truncated packet is received, this will lead to a buffer
underflow, reading memory before the start of the skb data area,
and causing a kernel panic.

Add length checks for both rtl8187 and rtl8187b descriptor headers
before attempting to access them, dropping the packet cleanly if the
check fails.

## Which versions are affected by CVE-2025-68362?


## How do I fix CVE-2025-68362?

Apply the vendor's patch.

## Is CVE-2025-68362 being exploited?

There is no known exploitation of CVE-2025-68362 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68362 and fix it if it is affected.

What it is: CVE-2025-68362 is a memory corruption vulnerability in Linux, published on 24 Dec 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-2025-68362 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-2025-68362/ (Markdown: https://insights.sbomify.com/CVE-2025-68362/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68362
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68362
- OSV: https://osv.dev/vulnerability/CVE-2025-68362

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68362/
Summaries are generated and may contain mistakes; the official description above is the record.