PackageKit Dnf5 Backend PrivEsc via SIMULATE Flag Bypass
CVE-2026-19816 Published on September 14, 2026

PackageKit: dnf5 backend ignores SIMULATE on RepoRemove
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.

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-19816 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, a high impact on integrity and availability.

Attack Vector:
LOCAL
Attack Complexity:
LOW
Privileges Required:
LOW
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
HIGH
Availability Impact:
HIGH

Weakness Type

What is an AuthZ Vulnerability?

The software performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

CVE-2026-19816 has been classified to as an AuthZ vulnerability or weakness.


Products Associated with CVE-2026-19816

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