CVE-2011-1083

The epoll implementation in the Linux kernel 2.6.37.2 and earlier does not properly traverse a tree of epoll file descriptors, which allows local users to cause a denial of service (CPU consumption) via a crafted application that makes epoll_create and epoll_ctl system calls.

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

Potential Mitigations

• Mitigation of resource exhaustion attacks requires that the target system either:

• The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.

• The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/147.html
• https://cwe.mitre.org/data/definitions/227.html
• https://cwe.mitre.org/data/definitions/492.html

References

• http://article.gmane.org/gmane.linux.kernel/1105744
• http://article.gmane.org/gmane.linux.kernel/1105888
• http://article.gmane.org/gmane.linux.kernel/1106686
• http://lists.opensuse.org/opensuse-security-announce/2012-04/msg00021.html
• http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00013.html
• http://openwall.com/lists/oss-security/2011/03/02/1
• http://openwall.com/lists/oss-security/2011/03/02/2
• http://rhn.redhat.com/errata/RHSA-2012-0862.html
• http://secunia.com/advisories/43522
• http://secunia.com/advisories/48115
• http://secunia.com/advisories/48410
• http://secunia.com/advisories/48898
• http://secunia.com/advisories/48964
• http://www.osvdb.org/71265
• https://bugzilla.redhat.com/show_bug.cgi?id=681578
• http://article.gmane.org/gmane.linux.kernel/1105744
• http://article.gmane.org/gmane.linux.kernel/1105888
• http://article.gmane.org/gmane.linux.kernel/1106686
• http://lists.opensuse.org/opensuse-security-announce/2012-04/msg00021.html
• http://lists.opensuse.org/opensuse-security-announce/2012-05/msg00013.html
• http://openwall.com/lists/oss-security/2011/03/02/1
• http://openwall.com/lists/oss-security/2011/03/02/2
• http://rhn.redhat.com/errata/RHSA-2012-0862.html
• http://secunia.com/advisories/43522
• http://secunia.com/advisories/48115
• http://secunia.com/advisories/48410
• http://secunia.com/advisories/48898
• http://secunia.com/advisories/48964
• http://www.osvdb.org/71265
• https://bugzilla.redhat.com/show_bug.cgi?id=681578