Description
Race condition in the do_add_counters function in netfilter for Linux kernel 2.6.16 allows local users with CAP_NET_ADMIN capabilities to read kernel memory by triggering the race condition in a way that produces a size value that is inconsistent with allocated memory, which leads to a buffer over-read in IPT_ENTRY_ITERATE.
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 3.1 | kernel-source-2.4.27 | 2.4.27-10sarge3 | DSA-1097-1 |
| Debian 3.1 | kernel-source-2.6.8 | 2.6.8-16sarge3 | DSA-1103 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 4 | kernel +8 | 2.6.9-42.0.3.EL | RHSA-2006:0689 |
Advisories 3
- RHSA-2006:0689 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1097-1 kernel-source-2.4.27 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1103 kernel-source-2.6.8 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- ADV-2006-2554 vdb-entry
- http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=2722971cbe831117686039d5c334f2c0f560be13
- ADV-2006-1893 vdb-entry
- 21476 third-party-advisory
- linux-doaddcounters-race-condition(26583) vdb-entry
- 22292 third-party-advisory
- RHSA-2006:0689 vendor-advisory
- oval:org.mitre.oval:def:10309 vdb-entry signature
- DSA-1097 vendor-advisory
- 20185 third-party-advisory
- http://kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.16.17
- USN-311-1 vendor-advisory
- DSA-1103 vendor-advisory
- 25697 vdb-entry
- http://support.avaya.com/elmodocs2/security/ASA-2006-249.htm
- https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=191698
- 22945 third-party-advisory
- 20991 third-party-advisory
- 20671 third-party-advisory
- http://bugs.gentoo.org/show_bug.cgi?id=133465
- 18113 vdb-entry
- 20914 third-party-advisory