CVE-2020-11933: local snapd exploit through cloud-init
Noroxi assessment
Priority: Monitor (action score 27/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.21% (FIRST EPSS).
- Physical access to the device is required. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to the record, no fixed version is available yet.
Low priority for now. Update when a fix is released; follow the vendor's advisory.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
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.
- Published
- Jul 29, 2020
- Updated
- Jun 16, 2026
- EPSS
- 0.2% · 12th percentile
- CWE
- CWE-264
Report tools
Action score
27
Monitor
Low priority for now.
- CVSS
- 27 / 40 · 6.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CNA vs NVD score
- NVD
- 6.8
- CNA · canonical
- 7.3
- 0.5 point gap
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- No fixed version yet
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| canonical | snapd | cpe:2.3:a:canonical:snapd |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical snapdbefore 2.45.2
- canonical ubuntu linux16.04
- canonical ubuntu linux18.04
- canonical ubuntu linux19.10
- canonical ubuntu linux20.04
Versions reported by the vendor
Affected version ranges reported by the assigning authority (canonical). Independent of NVD's CPE analysis and usually ahead of it.
Canonical core
- 2.45.2 and later · before 2.45.2, revision 9659affected
Canonical snapd
- 2.45.2 and later · before 2.45.2, revision 8539affected
Same product
canonical: all recordsOther highest-scoring records for the same primary product.
- CVE-2019-7304Local privilege escalation via snapd socket57Plan
- CVE-2023-1523Using the TIOCLINUX ioctl request, a malicious snap could inject contents into the input of the controlling terminal which could allow it to40Plan
- CVE-2020-27352When generating the systemd service units for the docker snap (and other similar snaps), snapd does not specify Delegate=yes - as a result s35Monitor
Published before and after this one in the same product
- ← EarlierCVE-2019-11502Apr 24, 2019 · snap-confine in snapd before 2.38 incorrectly set the ownership of a snap application to the uid and gid of the first calling user.31Monitor
- ← EarlierCVE-2019-11503Apr 24, 2019 · snap-confine as included in snapd before 2.39 did not guard against symlink races when performing the chdir() to the current working directo31Monitor
- Later →CVE-2021-3155Feb 17, 2022 · snapd created ~/snap with too-wide permissions22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Physical access to the device is required.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Physical
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-264 · Permissions, Privileges, and Access ControlsCVSS vector
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.