CVE-2021-3560Red Hat Polkit Incorrect Authorization Vulnerability
CVE-2021-3560 is a incorrect authorization in Red Hat Polkit, rated high (7.8 on CVSS 3.1).
Why this priority: Exploited in the wild: listed in CISA's KEV catalog.
Published · Updated · NVD status: Analyzed
What it is
A permission check exists but gets the answer wrong for some callers. An unusual condition is not handled, leaving the software in an unsafe state.
How it is reached
An attacker can exploit it by someone who can already run code or sign in on the machine, with an ordinary user account, and nobody has to click anything.
What an attacker gains
A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker reach data or actions their role should not allow.
Is it being exploited?
CISA added it to the Known Exploited Vulnerabilities catalog on 2023-05-12: it is being exploited in the wild. EPSS estimates a 22% chance of exploitation activity in the next 30 days, higher than 98% of scored CVEs.
What to do
- Treat it as urgent: it is on CISA's KEV list. CISA's deadline for US federal agencies: 2023-06-02.
- Upgrade Red Hat Polkit to 0.119 or later. The patch notes are linked below.
- Limit who can run code or sign in on the hosts that run it.
- Check exposed instances for signs of compromise, not only for the version.
Description from NVD
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.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Operating systems on servers, workstations or devices. Everything on the host inherits the flaw.
- Permission checks in APIs and admin surfaces. The flaw sits between one role or tenant and another.
- Multi-tenant services. The flaw sits between one role or tenant and another.
- Interfaces that accept external input. The flaw sits at the input boundary of the affected component.
Trust boundaries in play
- Host boundary. The attacker needs a foothold on the machine first; the flaw turns a small foothold into a bigger one.
- Between one role or tenant and another. An attacker who crosses it can reach data or actions their role should not allow.
- At the input boundary of the affected component. An attacker who crosses it can drive the component into behaviour its authors did not intend.
Questions to answer about your own systems
- Where does Red Hat Polkit run in your systems, and at which version?
- Which of those hosts also run code or users you do not fully trust?
- What can it reach once compromised: which data stores, secrets and services?
Read more
Patches and commits
Advisories
Exploits and proofs of concept
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.