Default inheritable capabilities for linux container should be empty
Moderate severity
GitHub Reviewed
Published
May 11, 2022
in
opencontainers/runc
•
Updated Mar 27, 2023
Description
Published by the National Vulnerability Database
May 17, 2022
Published to the GitHub Advisory Database
May 24, 2022
Reviewed
May 24, 2022
Last updated
Mar 27, 2023
Credits
-
AndrewGMorgan Analyst
Impact
A bug was found in runc where
runc exec --capexecuted processes with non-empty inheritable Linux process capabilities, creating an atypical Linux environment and enabling programs with inheritable file capabilities to elevate those capabilities to the permitted set during execve(2).This bug did not affect the container security sandbox as the inheritable set never contained more capabilities than were included in the container's bounding set.
Patches
This bug has been fixed in runc 1.1.2. Users should update to this version as soon as possible.
This fix changes
runc exec --capbehavior such that the additional capabilities granted to the process being executed (as specified via--caparguments) do not include inheritable capabilities.In addition,
runc specis changed to not set any inheritable capabilities in the created example OCI spec (config.json) file.Credits
The opencontainers project would like to thank Andrew G. Morgan for responsibly disclosing this issue in accordance with the opencontainers org security policy.
For more information
If you have any questions or comments about this advisory:
References