# CVE-2025-39716: parisc: Revise __get_user() to probe user read access

> A flaw in the Linux kernel parisc architecture allows user code to access read-protected memory via system calls, potentially leading to privilege escalation or data exposure.

- **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:** 5 Sep 2025
- **Updated:** 12 May 2026
- **Also known as:** AZL-67013, AZL-73662, BELL-CVE-2025-39716, DEBIAN-CVE-2025-39716, GHSA-pv37-x56g-xg2m, ROOT-OS-DEBIAN-11-CVE-2025-39716, ROOT-OS-DEBIAN-12-CVE-2025-39716, ROOT-OS-DEBIAN-13-CVE-2025-39716, ROOT-OS-UBUNTU-2204-CVE-2025-39716, ROOT-OS-UBUNTU-2404-CVE-2025-39716, UBUNTU-CVE-2025-39716

## What is CVE-2025-39716?

CVE-2025-39716 is a medium-severity vulnerability in Debian Debian Linux, published on 5 Sep 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:

parisc: Revise __get_user() to probe user read access

Because of the way read access support is implemented, read access
interruptions are only triggered at privilege levels 2 and 3. The
kernel executes at privilege level 0, so __get_user() never triggers
a read access interruption (code 26). Thus, it is currently possible
for user code to access a read protected address via a system call.

Fix this by probing read access rights at privilege level 3 (PRIV_USER)
and setting __gu_err to -EFAULT (-14) if access isn't allowed.

Note the cmpiclr instruction does a 32-bit compare because COND macro
doesn't work inside asm.

## Which versions are affected by CVE-2025-39716?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-39716?

Apply the vendor's patch.

## Is CVE-2025-39716 being exploited?

There is no known exploitation of CVE-2025-39716 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-39716 and fix it if it is affected.

What it is: CVE-2025-39716 is a medium-severity vulnerability in Debian Debian Linux, published on 5 Sep 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-2025-39716 in the wild and no public exploit code.

Affected product: Debian Debian 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-2025-39716/ (Markdown: https://insights.sbomify.com/CVE-2025-39716/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-39716
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-39716
- OSV: https://osv.dev/vulnerability/CVE-2025-39716

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-39716/
Summaries are generated and may contain mistakes; the official description above is the record.