How severe is CVE-2021-41103?

CVE-2021-41103 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-41103?

CVE-2021-41103 affects the following packages: github.com/containerd/containerd (Go), github.com/containerd/containerd (Go). Ecosystems affected: Go.

How do I fix CVE-2021-41103?

Update github.com/containerd/containerd to 1.4.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41103 is resolved across your whole dependency graph.

How do I detect CVE-2021-41103 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/containerd/containerd, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-41103 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2021-41103 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-41103 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-41103?

CVE-2021-41103 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 42th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-41103?

CVE-2021-41103 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2021-41103 published, and has it been updated?

CVE-2021-41103 was published on October 4, 2021 and was last updated on July 8, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

HIGH severity

CVE-2021-41103 — containerd

HIGHFix: containerd/containerd@5b46e40

CVE-2021-41103 is a high-severity (CVSS 7.8) Path Traversal vulnerability in github.com/containerd/containerd. A fix is available for github.com/containerd/containerd — see the affected versions and patch details below.

Insufficiently restricted permissions on plugin directories

Also known asGHSA-c2h3-6mxw-7mvqGO-2022-0938

Published

Oct 4, 2021

Updated

Jul 8, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Oct 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs42th percentile — riskier than 42% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2021-41103 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

2 pkgs affected

🐹github.com/containerd/containerd🐹github.com/containerd/containerd

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

A bug was found in containerd where container root directories and some plugins had 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.

Patches

This vulnerability has been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are released and may restart containers or update directory permissions to mitigate the vulnerability.

Workarounds

Limit access to the host to trusted users. Update directory permission on container bundles directories.

For more information

If you have any questions or comments about this advisory:

Open an issue in github.com/containerd/containerd
Email us at [email protected]

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/containerd/containerd`	all versions	1.4.11`go get github.com/containerd/containerd@v1.4.11`
🐹Go	`github.com/containerd/containerd`	≥ 1.5.0&&< 1.5.7	1.5.7`go get github.com/containerd/containerd@v1.5.7`

Affected Products

3 products · 5 configurations

debian linuxdebian

1 version

11.0

fedorafedoraproject

2 versions

3435

Application

containerdlinuxfoundation

≥ 1.5.0 && < 1.5.7

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/containerd/containerd, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/containerd/containerd to 1.4.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41103 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Product	Fixed in	Advisory
Red Hat OpenStack Platform 16.2	`rhosp-rhel8-tech-preview/osp-director-operator:1.2.3-3`	RHSA-2022:5673
Red Hat OpenStack Platform 16.2	`rhosp-rhel8-tech-preview/osp-director-operator:1.2.3-4`	RHSA-2022:6517

UbuntuHIGH

USN-5100-1Ubuntu USN-5521-1Ubuntu

Frequently Asked Questions

### Impact A bug was found in containerd where container root directories and some plugins had 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. ### Patc