CVE-2020-11933 local snapd exploit through cloud-init
A physical attacker can bypass full disk encryption on Ubuntu Core devices by exploiting unrestricted cloud-init execution during boot via external media.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2020-11933?
CVE-2020-11933 is a high-severity vulnerability in Canonical Ubuntu Linux, published on 29 Jul 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
cloud-init as managed by snapd on Ubuntu Core 16 and Ubuntu Core 18 devices was run without restrictions on every boot, which a physical attacker could exploit by crafting cloud-init user-data/meta-data via external media to perform arbitrary changes on the device to bypass intended security mechanisms such as full disk encryption. This issue did not affect traditional Ubuntu systems. Fixed in snapd version 2.45.2, revision 8539 and core version 2.45.2, revision 9659.
Weakness: CWE-264
Which versions are affected by CVE-2020-11933?
It affects 2 products.
Products include Canonical Snapd, Canonical Ubuntu Linux.
How do I fix CVE-2020-11933?
No fix has been published for CVE-2020-11933 yet. Limit exposure of the affected software until one is available.
Is CVE-2020-11933 being exploited?
There is no known exploitation of CVE-2020-11933 in the wild and no public exploit code.
Other vulnerabilities in Canonical Ubuntu Linux
- CVE-2023-1523 Command injection in snapd
- CVE-2020-27352 Privilege escalation in snapd
- CVE-2019-7304 Local privilege escalation via snapd socket
- CVE-2021-4120 snapd could be made to bypass intended access restrictions through snap content interfaces and layout paths
- CVE-2024-5138 CVE-2024-5138: snapd snapctl auth bypass
Sources
Also known as GHSA-v343-8p34-76p3.