local snapd exploit through cloud-init

published 2020-07-29 6y ago modified 2026-06-17 4mo ago also EUVD-2020-4270

cvss: 7.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 12%
public exploits: 0; none known

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.

Patch / fix

fixed in 2

Canonical snapd 2.45.2, revision 8539
Canonical core 2.45.2, revision 9659

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Exploit prediction

0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.3	CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
NVD	3.1	6.8	CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	4.6	AV:L/AC:L/Au:N/C:P/I:P/A:P

Affected products

Canonical snapd
Canonical core

Classification

Weakness

CWE-264 Permissions, Privileges, and Access Controls

References

ubuntu.com /USN-4424-1
vendor-advisory
launchpad.net /bugs/1879530
third-party-advisory

Sources

CVE List CVE-2020-11933
NVD CVE-2020-11933

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