Insufficiently restricted permissions on plugin directories (CVE-2021-41103)

Why this deserves its current priority

CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps github.com/containerd/containerd (go), github.com/containerd/containerd (go). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
github.com/containerd/containerdgo	>=0 <1.4.11	1.4.11
github.com/containerd/containerdgo	>=1.5.0 <1.5.7	1.5.7

Recommended response

Check inventory. Check lockfiles and deployed manifests for github.com/containerd/containerd, github.com/containerd/containerd.
Review the reported fix. Update github.com/containerd/containerd to 1.4.11; github.com/containerd/containerd to 1.5.7 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 4, 2021
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Sep 10, 2026

Sources and claim methodology

Upstream source 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](https://github.com/containerd/containerd/issues/new/choose) * Email us at [[email protected]](mailto:[email protected])

Quoted source text, attributed separately from HOL analysis.