Description
The tcp_illinois_info function in net/ipv4/tcp_illinois.c in the Linux kernel before 3.4.19, when the net.ipv4.tcp_congestion_control illinois setting is enabled, allows local users to cause a denial of service (divide-by-zero error and OOPS) by reading TCP stats.
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 14 | linux | 3.2.35-1 | — |
| Debian 13 | linux | 3.2.35-1 | — |
| Debian 12 | linux | 3.2.35-1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | perf +15 | 2.6.32-279.19.1.el6 | RHSA-2012:1580 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat MRG 2 | kernel-rt +11 | 3.2.33-rt50.66.el6rt | RHSA-2012:1491 |
Advisories 2
- RHSA-2012:1491 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jul 20, 2026
- RHSA-2012:1580 Red Hat Security Advisory: kernel security, bug fix and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
References
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=8f363b77ee4fbf7c3bbcf5ec2c5ca482d396d664
- USN-1644-1 vendor-advisory
- USN-1645-1 vendor-advisory
- http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.4.19
- USN-1647-1 vendor-advisory
- RHSA-2012:1580 vendor-advisory
- USN-1652-1 vendor-advisory
- https://github.com/torvalds/linux/commit/8f363b77ee4fbf7c3bbcf5ec2c5ca482d396d664
- https://bugzilla.redhat.com/show_bug.cgi?id=871848
- USN-1646-1 vendor-advisory
- USN-1651-1 vendor-advisory
- FEDORA-2012-17479 vendor-advisory
- USN-1648-1 vendor-advisory
- 56346 vdb-entry
- [oss-security] 20121031 Re: CVE Request -- kernel: net: divide by zero in tcp algorithm illinois mailing-list
- USN-1649-1 vendor-advisory
- USN-1650-1 vendor-advisory
- 51409 third-party-advisory