# CVE-2026-19816: PackageKit: dnf5 backend ignores SIMULATE on RepoRemove

> An unprivileged local user can bypass simulation checks to perform real package uninstalls in systems using PackageKit with the dnf5 backend.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/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:** 14 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-19816, GHSA-g5gf-h68q-gxc8, openSUSE-SU-2026:11855-1

## What is CVE-2026-19816?

CVE-2026-19816 is a high-severity vulnerability in Fedora, published on 14 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in PackageKit. PackageKit skips the polkit authorization check for transactions carrying the SIMULATE (dry-run) flag. In the dnf5 backend, the RepoRemove handler ignores that contract and always executes the real transaction because its guard is written as (role == REPO_REMOVE || !SIMULATE), which is always true for RepoRemove. An unprivileged local user can therefore perform a genuine package uninstall while claiming to simulate. This vulnerability only affects systems using PackageKit with the dnf5 backend.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-19816?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `PackageKit` | openSUSE:Tumbleweed | All versions | 1.4.0-1.1 |

## How do I fix CVE-2026-19816?

Apply the vendor's patch.

## Is CVE-2026-19816 being exploited?

There is no known exploitation of CVE-2026-19816 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-19816 and fix it if it is affected.

What it is: CVE-2026-19816 is a high-severity vulnerability in Fedora, published on 14 Sep 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-2026-19816 in the wild and no public exploit code.

Affected product: Fedora. 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-2026-19816/ (Markdown: https://insights.sbomify.com/CVE-2026-19816/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-19816
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-19816
- OSV: https://osv.dev/vulnerability/CVE-2026-19816

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-19816/
Summaries are generated and may contain mistakes; the official description above is the record.