CVE-2011-2525

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: none known
Published: 2012-02-02 · updated 2026-06-16
Weakness: CWE-476

Description

The qdisc_notify function in net/sched/sch_api.c in the Linux kernel before 2.6.35 does not prevent tc_fill_qdisc function calls referencing builtin (aka CQ_F_BUILTIN) Qdisc structures, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) or possibly have unspecified other impact via a crafted call.

Affected products

Linux kernel: before 2.6.35 — fixed in 2.6.35
Red Hat Enterprise Linux: 4.0

How to fix

Upgrade to a fixed version: Linux kernel 2.6.35. Check the vendor advisory for mitigations.

References

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=53b0f08042f04813cd1a7473dacd3edfacb28eb3
http://kerneltrap.org/mailarchive/linux-netdev/2010/5/21/6277805
http://mirror.anl.gov/pub/linux/kernel/v2.6/ChangeLog-2.6.35
http://openwall.com/lists/oss-security/2011/07/12/1
http://rhn.redhat.com/errata/RHSA-2011-1065.html
http://rhn.redhat.com/errata/RHSA-2011-1163.html
https://bugzilla.redhat.com/show_bug.cgi?id=720552
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=53b0f08042f04813cd1a7473dacd3edfacb28eb3
http://kerneltrap.org/mailarchive/linux-netdev/2010/5/21/6277805
http://mirror.anl.gov/pub/linux/kernel/v2.6/ChangeLog-2.6.35
http://openwall.com/lists/oss-security/2011/07/12/1
http://rhn.redhat.com/errata/RHSA-2011-1065.html

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