CVE-2011-1771

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2011-09-06 · updated 2026-06-16
Weakness: CWE-476

Description

The cifs_close function in fs/cifs/file.c in the Linux kernel before 2.6.39 allows local users to cause a denial of service (NULL pointer dereference and BUG) or possibly have unspecified other impact by setting the O_DIRECT flag during an attempt to open a file on a CIFS filesystem.

Affected products

Linux kernel: before 2.6.39 — fixed in 2.6.39

How to fix

Upgrade to a fixed version: Linux kernel 2.6.39. Check the vendor advisory for mitigations.

References

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=7797069305d13252fd66cf722aa8f2cbeb3c95cd
http://marc.info/?l=linux-cifs&m=130204357001849&w=2
http://marc.info/?l=linux-cifs&m=130204730006155&w=2
http://securityreason.com/securityalert/8367
http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39
http://www.openwall.com/lists/oss-security/2011/05/09/2
https://bugzilla.redhat.com/show_bug.cgi?id=703016
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=7797069305d13252fd66cf722aa8f2cbeb3c95cd
http://marc.info/?l=linux-cifs&m=130204357001849&w=2
http://marc.info/?l=linux-cifs&m=130204730006155&w=2
http://securityreason.com/securityalert/8367
http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39

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