# CVE-2022-49803: netdevsim: Fix memory leak of nsim_dev->fa_cookie

> A memory leak in the Linux kernel netdevsim driver allows local attackers to exhaust system memory, potentially causing a denial of service.

- **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:** 1 May 2025
- **Updated:** 4 Jul 2026
- **Also known as:** AZL-69785, DEBIAN-CVE-2022-49803, GHSA-whrx-8qvw-6p89, ROOT-OS-DEBIAN-11-CVE-2022-49803, ROOT-OS-UBUNTU-2204-CVE-2022-49803, UBUNTU-CVE-2022-49803

## What is CVE-2022-49803?

CVE-2022-49803 is a medium-severity memory corruption vulnerability in Linux kernel, published on 1 May 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:

netdevsim: Fix memory leak of nsim_dev->fa_cookie

kmemleak reports this issue:

unreferenced object 0xffff8881bac872d0 (size 8):
  comm "sh", pid 58603, jiffies 4481524462 (age 68.065s)
  hex dump (first 8 bytes):
    04 00 00 00 de ad be ef                          ........
  backtrace:
    [<00000000c80b8577>] __kmalloc+0x49/0x150
    [<000000005292b8c6>] nsim_dev_trap_fa_cookie_write+0xc1/0x210 [netdevsim]
    [<0000000093d78e77>] full_proxy_write+0xf3/0x180
    [<000000005a662c16>] vfs_write+0x1c5/0xaf0
    [<000000007aabf84a>] ksys_write+0xed/0x1c0
    [<000000005f1d2e47>] do_syscall_64+0x3b/0x90
    [<000000006001c6ec>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

The issue occurs in the following scenarios:

nsim_dev_trap_fa_cookie_write()
  kmalloc() fa_cookie
  nsim_dev->fa_cookie = fa_cookie
..
nsim_drv_remove()

The fa_cookie allocked in nsim_dev_trap_fa_cookie_write() is not freed. To
fix, add kfree(nsim_dev->fa_cookie) to nsim_drv_remove().

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2022-49803?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49803?

Apply the vendor's patch.

## Is CVE-2022-49803 being exploited?

There is no known exploitation of CVE-2022-49803 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-2022-49803 and fix it if it is affected.

What it is: CVE-2022-49803 is a medium-severity memory corruption vulnerability in Linux kernel, published on 1 May 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-2022-49803 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-2022-49803/ (Markdown: https://insights.sbomify.com/CVE-2022-49803/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49803
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49803
- OSV: https://osv.dev/vulnerability/CVE-2022-49803

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49803/
Summaries are generated and may contain mistakes; the official description above is the record.