CVE-2021-41091
MEDIUMEPSS 86th pctlDescription
Moby is an open-source project created by Docker to enable software containerization. A bug was found in Moby (Docker Engine) where the data directory (typically `/var/lib/docker`) contained subdirectories with insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as `setuid`), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files. This bug has been fixed in Moby (Docker Engine) 20.10.9. Users should update to this version as soon as possible. Running containers should be stopped and restarted for the permissions to be fixed. For users unable to upgrade limit access to the host to trusted users. Limit access to host volumes to trusted containers.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L
Exploit Intelligence
Elevated risk: more likely to be exploited than 86% of all known CVEs.
References
Related Vulnerabilities
Other CWE-281 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2017-8543 | Critical | 9.8 | 74% | KEV | - |
| CVE-2019-0233 | High | 7.5 | 68% | - | - |
| CVE-2017-8589 | Critical | 9.8 | 24% | - | - |
| CVE-2021-33990 | Critical | 9.8 | 12% | - | - |
| CVE-2017-8578 | High | 7.8 | 6.3% | - | - |
| CVE-2017-8563 | High | 8.1 | 5.9% | - | - |
Common questions
How do I fix CVE-2021-41091?
Upgrade docker.io on debian 11 to 20.10.5+dfsg1-1+deb11u1 or later.
Is CVE-2021-41091 being actively exploited?
Not that we know of. CVE-2021-41091 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 2.8% is the estimated probability that it will be exploited in the next 30 days. That is higher than 86% of all scored CVEs.
How severe is CVE-2021-41091?
CVE-2021-41091 has a CVSS v3 base score of 6.3, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-41091 affect?
Published advisories record a fix for docker.io (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2021-41091
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.