CVE-2021-44730: snapd 2.54.2 did not properly validate the location of the snap-confine binary

Q: How do I fix CVE-2021-44730?

snapd: upgrade to newer than 2.54.2; ubuntu linux: mitigate or apply the listed mitigation; fedora: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Q: Is CVE-2021-44730 being exploited?

CVE-2021-44730 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2021-44730 affect?

CVE-2021-44730 affects snapd, ubuntu linux, fedora. Severity is high (CVSS 7.8). snapd 2.54.2 did not properly validate the location of the snap-confine binary. A local attacker who can hardlink this binary to another location to cause snap-confine to execute other arbitrary binaries and hence gain privilege escalation.

Q: How urgent is CVE-2021-44730?

Priority 39/100. High severity; On your watchlist

Routine

HIGH 7.8WATCHLISTUPGRADEMITIGATEMITIGATE

CVE-2021-44730 is a high-severity flaw (CVSS 7.8) affecting snapd, ubuntu linux, fedora. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

snapd 2.54.2 did not properly validate the location of the snap-confine binary. A local attacker who can hardlink this binary to another location to cause snap-confine to execute other arbitrary binaries and hence gain privilege escalation. Fixed in snapd versions 2.54.3+18.04, 2.54.3+20.04 and 2.54.3+21.10.1

Why this priority

High severity
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	7.8 (High)
Attack vector	Local
Attack complexity	High
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.4% (top 71%)
CISA exploited list	No
Weakness	CWE-59
Published	2022-02-17
Last modified	2026-06-17

Publisher (CNA): Canonical Ltd. · Vendor: canonical · debian · fedoraproject

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-02-17 23:15 UTCPublished CVE record published
2026-06-17 04:12 UTCUpdated Record last modified

canonical snapd UPGRADE

Affected: <= 2.54.2

Fixed in: newer than 2.54.2

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy snapd || rpm -q snapd || snapd --version

2. UPGRADE to newer than 2.54.2 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade snapd

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade snapd

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

canonical ubuntu linux MITIGATE

Affected: 18.04 · 20.04 · 21.10

Fixed in: no fixed release known

Safe to downgrade to: a release before 18.04

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

fedoraproject fedora MITIGATE

Affected: 34 · 35

Fixed in: no fixed release known

Safe to downgrade to: a release before 34

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

debian debian linux MITIGATE

Affected: 10.0 · 11.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 10.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-44730?

snapd: upgrade to newer than 2.54.2; ubuntu linux: mitigate or apply the listed mitigation; fedora: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-44730 being exploited?

CVE-2021-44730 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-44730 affect?

CVE-2021-44730 affects snapd, ubuntu linux, fedora. Severity is high (CVSS 7.8). snapd 2.54.2 did not properly validate the location of the snap-confine binary. A local attacker who can hardlink this binary to another location to cause snap-confine to execute other arbitrary binaries and hence gain privilege escalation.

How urgent is CVE-2021-44730?

Priority 39/100. High severity; On your watchlist

Software pages

Ubuntu vulnerabilities · Debian vulnerabilities

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References

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