# CVE-2026-53388: fuse: re-lock request before replacing page cache folio

> A use-after-free vulnerability in the Linux kernel's FUSE filesystem allows attackers to potentially execute code or escalate privileges.

- **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:** 19 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-53388, DEBIAN-CVE-2026-53388, GHSA-45w6-5frg-3vfq, ROOT-OS-DEBIAN-11-CVE-2026-53388, ROOT-OS-UBUNTU-2204-CVE-2026-53388, UBUNTU-CVE-2026-53388

## What is CVE-2026-53388?

CVE-2026-53388 is a high-severity use after free vulnerability in Linux kernel, published on 19 Jul 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:

fuse: re-lock request before replacing page cache folio

fuse_try_move_folio() unlocks the request on entry but does not
re-lock it on the success path. This means fuse_chan_abort() can end the
request and free the fuse_io_args (eg fuse_readpages_end()) while the
subsequent copy chain logic after fuse_try_move_folio() accesses the
fuse_io_args, leading to use-after-free issues.

Fix this by calling lock_request() before replace_page_cache_folio().
This ensures the request is locked on the success path which will
prevent the fuse_io_args from being freed while the later copying logic
runs, and also ensures that the ap->folios[i]->mapping is never null
since ap->folios[i] will always point to the newfolio after
replace_page_cache_folio().

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-53388?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53388?

Apply the vendor's patch.

## Is CVE-2026-53388 being exploited?

There is no known exploitation of CVE-2026-53388 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-2026-53388 and fix it if it is affected.

What it is: CVE-2026-53388 is a high-severity use after free vulnerability in Linux kernel, published on 19 Jul 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-2026-53388 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-2026-53388/ (Markdown: https://insights.sbomify.com/CVE-2026-53388/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53388
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53388
- OSV: https://osv.dev/vulnerability/CVE-2026-53388

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53388/
Summaries are generated and may contain mistakes; the official description above is the record.