Description
The cifs_find_smb_ses function in fs/cifs/connect.c in the Linux kernel before 2.6.36 does not properly determine the associations between users and sessions, which allows local users to bypass CIFS share authentication by leveraging a mount of a share by a different user.
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 6.0 | linux-2.6 | 2.6.32-34squeeze1 | DSA-2240-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | kernel +11 | 2.6.18-274.7.1.el5 | RHSA-2011:1386 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat MRG 2 | kernel-rt +10 | 2.6.33.9-rt31.75.el6rt | RHSA-2011:1253 |
Advisories 3
- RHSA-2011:1386 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2011:1253 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- DSA-2240-1 linux-2.6 - several issues Debian Security (DSA / DLA) · Mar 9, 2026
References
- http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.36
- [oss-security] 20110415 Re: CVE Request: cifs session reuse mailing-list
- https://bugzilla.redhat.com/show_bug.cgi?id=697394
- https://github.com/torvalds/linux/commit/4ff67b720c02c36e54d55b88c2931879b7db1cd2
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=4ff67b720c02c36e54d55b88c2931879b7db1cd2
- SUSE-SU-2015:0812 vendor-advisory