Description
The do_change_type function in fs/namespace.c in the Linux kernel before 2.6.22 does not verify that the caller has the CAP_SYS_ADMIN capability, which allows local users to gain privileges or cause a denial of service by modifying the properties of a mountpoint.
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 4.0 | fai-kernels | 1.17+etch.22etch2 | DSA-1630-1 |
| Debian 4.0 | linux-2.6 | 2.6.18.dfsg.1-22etch2 | DSA-1630-1 |
| Debian 4.0 | user-mode-linux | 2.6.18-1um-2etch.22etch2 | DSA-1630-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | kernel +12 | 2.6.18-92.1.13.el5 | RHSA-2008:0885 |
Advisories 2
- RHSA-2008:0885 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1630-1 fai-kernels linux-2.6 user-mode-linux - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- DSA-1630 vendor-advisory
- linux-kernel-dochangetype-priv-escalation(43696) vdb-entry
- RHSA-2008:0885 vendor-advisory
- SUSE-SA:2008:038 vendor-advisory
- USN-637-1 vendor-advisory
- oval:org.mitre.oval:def:10437 vdb-entry signature
- SUSE-SA:2008:035 vendor-advisory
- 31614 third-party-advisory
- 30982 third-party-advisory
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commitdiff%3Bh=ee6f958291e2a768fd727e7a67badfff0b67711a
- [oss-security] 20080708 Re: CVE-2008-2931 kernel: missing check before setting mount propagation mailing-list
- 31551 third-party-advisory
- 30126 vdb-entry
- 32023 third-party-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=454388
- 32759 third-party-advisory
- http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.22
- [oss-security] 20080708 CVE-2008-2931 kernel: missing check before setting mount propagation mailing-list
- SUSE-SA:2008:049 vendor-advisory
- SUSE-SR:2008:025 vendor-advisory