policykit-1 vulnerabilities

UBUNTU-CVE-2026-85498

[Regression in CVE-2026-4897 fix (polkit read_cookie()) - stack buffer underflow]

Polkit: polkit: denial of service via unbounded input processing through standard input

A flaw was found in polkit. A local user can exploit this by providing a specially crafted, excessively long input to the `polkit-agent-helper-1` setuid binary via standard input (stdin). This unbounded input can lead to an out-of-memory (OOM) condition, resulting in a Denial of Service (DoS) for the system.

• Update to 127-3

Polkit: xml policy file with a large number of nested elements may lead to out-of-bounds write

A flaw was found in polkit. When processing an XML policy with 32 or more nested elements in depth, an out-of-bounds write can be triggered. This issue can lead to a crash or other unexpected behavior, and arbitrary code execution is not discarded. To exploit this flaw, a high-privilege account is needed as it's required to place the malicious policy file properly.

• Update to 127-1

CVE-2021-4115

There is a flaw in polkit which can allow an unprivileged user to cause polkit to crash, due to process file descriptor exhaustion. The highest threat from this vulnerability is to availability. NOTE: Polkit process outage duration is tied to the failing process being reaped and a new one being spawned

• Update to 0.105-32

CVE-2021-3560

It was found that polkit could be tricked into bypassing the credential checks for D-Bus requests, elevating the privileges of the requestor to the root user. This flaw could be used by an unprivileged local attacker to, for example, create a new local administrator. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

• Update to 0.105-31

CVE-2021-4034

A local privilege escalation vulnerability was found on polkit's pkexec utility. The pkexec application is a setuid tool designed to allow unprivileged users to run commands as privileged users according predefined policies. The current version of pkexec doesn't handle the calling parameters count correctly and ends trying to execute environment variables as commands. An attacker can leverage this by crafting environment variables in such a way it'll induce pkexec to execute arbitrary code. When successfully executed the attack can cause a local privilege escalation given unprivileged users administrative rights on the target machine.

• Update to 0.105-31.1

CVE-2019-6133

In PolicyKit (aka polkit) 0.115, the "start time" protection mechanism can be bypassed because fork() is not atomic, and therefore authorization decisions are improperly cached. This is related to lack of uid checking in polkitbackend/polkitbackendinteractiveauthority.c.

• Update to 0.105-25

CVE-2018-19788

A flaw was found in PolicyKit (aka polkit) 0.115 that allows a user with a uid greater than INT_MAX to successfully execute any systemctl command.

• Update to 0.105-23

CVE-2018-1116

A flaw was found in polkit before version 0.116. The implementation of the polkit_backend_interactive_authority_check_authorization function in polkitd allows to test for authentication and trigger authentication of unrelated processes owned by other users. This may result in a local DoS and information disclosure.

• Update to 0.105-21

CVE-2016-2568

pkexec, when used with --user nonpriv, allows local users to escape to the parent session via a crafted TIOCSTI ioctl call, which pushes characters to the terminal's input buffer.

• Update to 123-1

CVE-2015-4625

Integer overflow in the authentication_agent_new_cookie function in PolicyKit (aka polkit) before 0.113 allows local users to gain privileges by creating a large number of connections, which triggers the issuance of a duplicate cookie value.

• Update to 0.105-12

CVE-2015-3255

The polkit_backend_action_pool_init function in polkitbackend/polkitbackendactionpool.c in PolicyKit (aka polkit) before 0.113 might allow local users to gain privileges via duplicate action IDs in action descriptions.

• Update to 0.105-12

CVE-2015-3218

The authentication_agent_new function in polkitbackend/polkitbackendinteractiveauthority.c in PolicyKit (aka polkit) before 0.113 allows local users to cause a denial of service (NULL pointer dereference and polkitd daemon crash) by calling RegisterAuthenticationAgent with an invalid object path.

• Update to 0.105-11

CVE-2013-4288

Race condition in PolicyKit (aka polkit) allows local users to bypass intended PolicyKit restrictions and gain privileges by starting a setuid or pkexec process before the authorization check is performed, related to (1) the polkit_unix_process_new API function, (2) the dbus API, or (3) the --process (unix-process) option for authorization to pkcheck.

• Update to 0.105-3+nmu1

CVE-2011-4945

PolicyKit 0.103 sets the AdminIdentities to "wheel" by default, which allows local users in the wheel group to gain root privileges without authentication.

• Update to 0.103-1

CVE-2011-1485

Race condition in the pkexec utility and polkitd daemon in PolicyKit (aka polkit) 0.96 allows local users to gain privileges by executing a setuid program from pkexec, related to the use of the effective user ID instead of the real user ID.

• Update to 0.101-4

CVE-2008-1658

Format string vulnerability in the grant helper (polkit-grant-helper.c) in PolicyKit 0.7 and earlier allows attackers to cause a denial of service (crash) and possibly execute arbitrary code via format strings in a password.

• Update to 0.8-1