# CVE-2026-31730: misc: fastrpc: possible double-free of cctx->remote_heap

> A double-free vulnerability in the Linux kernel fastrpc driver allows attackers to potentially execute code or escalate privileges via specific ioctl and device removal sequences.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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 2026
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2026-31730, DEBIAN-CVE-2026-31730, GHSA-8r84-g6v2-vrq6, ROOT-OS-UBUNTU-2404-CVE-2026-31730, UBUNTU-CVE-2026-31730

## What is CVE-2026-31730?

CVE-2026-31730 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 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:

misc: fastrpc: possible double-free of cctx->remote_heap

fastrpc_init_create_static_process() may free cctx->remote_heap on the
err_map path but does not clear the pointer. Later, fastrpc_rpmsg_remove()
frees cctx->remote_heap again if it is non-NULL, which can lead to a
double-free if the INIT_CREATE_STATIC ioctl hits the error path and the rpmsg
device is subsequently removed/unbound.
Clear cctx->remote_heap after freeing it in the error path to prevent the
later cleanup from freeing it again.

This issue was found by an in-house analysis workflow that extracts AST-based
information and runs static checks, with LLM assistance for triage, and was
confirmed by manual code review.
No hardware testing was performed.

Weakness: CWE-415 (Double Free)

## Which versions are affected by CVE-2026-31730?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31730?

Apply the vendor's patch.

## Is CVE-2026-31730 being exploited?

There is no known exploitation of CVE-2026-31730 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-2026-31730 and fix it if it is affected.

What it is: CVE-2026-31730 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 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-2026-31730 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-2026-31730/ (Markdown: https://insights.sbomify.com/CVE-2026-31730/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31730
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31730
- OSV: https://osv.dev/vulnerability/CVE-2026-31730

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31730/
Summaries are generated and may contain mistakes; the official description above is the record.