Description
The clone_mnt function in fs/namespace.c in the Linux kernel before 3.8.6 does not properly restrict changes to the MNT_READONLY flag, which allows local users to bypass an intended read-only property of a filesystem by leveraging a separate mount namespace.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 3.8.13-1 | — |
| Debian 13 | linux | 3.8.13-1 | — |
| Debian 12 | linux | 3.8.13-1 | — |
References
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=132c94e31b8bca8ea921f9f96a57d684fa4ae0a9
- [oss-security] 20130416 Re: Re: Summary of security bugs (now fixed) in user namespaces mailing-list
- http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.8.6
- https://github.com/torvalds/linux/commit/132c94e31b8bca8ea921f9f96a57d684fa4ae0a9