Red Hat Bugzilla – Bug 689337
CVE-2011-2534 ipv4: netfilter: ipt_CLUSTERIP: fix buffer overflow
Last modified: 2015-08-19 05:09:05 EDT
'buffer' string is copied from userspace. It is not checked whether it is zero terminated. This may lead to overflow inside of simple_strtoul(). Changli Gao suggested to copy not more than user supplied 'size' bytes. It was introduced before the git epoch. Files "ipt_CLUSTERIP/*" are root writable only by default, however, on some setups permissions might be relaxed to e.g. network admin user. http://marc.info/?l=netfilter-devel&m=130036157327564&w=2 Proposed patch: http://git.kernel.org/?p=linux/kernel/git/kaber/nf-2.6.git;a=commitdiff;h=961ed183a9fd080cf306c659b8736007e44065a5 Acknowledgements: Red Hat would like to thank Vasiliy Kulikov of Openwall for reporting this issue.
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=961ed183a9fd080cf306c659b8736007e44065a5
Didn't assign a CVE name for this one as the default perms for this is S_IWUSR|S_IRUSR. But MITRE might assign one.
(In reply to comment #4) > Didn't assign a CVE name for this one as the default perms for this is > S_IWUSR|S_IRUSR. But MITRE might assign one. Common Vulnerabilities and Exposures assigned an identifier CVE-2011-2534 to the following vulnerability: Buffer overflow in the clusterip_proc_write function in net/ipv4/netfilter/ipt_CLUSTERIP.c in the Linux kernel before 2.6.39 might allow local users to cause a denial of service or have unspecified other impact via a crafted write operation, related to string data that lacks a terminating '\0' character. References: [1] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-2534 [2] http://marc.info/?l=netfilter-devel&m=130036157327564&w=2 [3] http://marc.info/?l=netfilter&m=129978077509888&w=2 [4] http://www.openwall.com/lists/oss-security/2011/03/18/15 [5] http://www.openwall.com/lists/oss-security/2011/03/21/4 [6] http://www.openwall.com/lists/oss-security/2011/03/21/1 [7] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=961ed183a9fd080cf306c659b8736007e44065a5 [8] http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39
Statement: This issue did not affect the version of Linux kernel as shipped with Red Hat Enterprise Linux 4 as it did not have support for ipt_CLUSTERIP. This has been addressed in Red Hat Enterprise Linux 5, 6, and Red Hat Enterprise MRG via http://rhn.redhat.com/errata/RHSA-2011-0833.html, http://rhn.redhat.com/errata/RHSA-2011-0498.html, and http://rhn.redhat.com/errata/RHSA-2011-0500.html.