Description
net/ipv6/tcp_ipv6.c in Linux kernel 2.6.x up to 2.6.21-rc3 inadvertently copies the ipv6_fl_socklist from a listening TCP socket to child sockets, which allows local users to cause a denial of service (OOPS) or double free by opening a listening IPv6 socket, attaching a flow label, and connecting to that socket.
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 4.0 | linux-2.6 | 2.6.18.dfsg.1-12etch1 | DSA-1286-1 |
| Debian 3.1 | hostap-modules-i386 | 1:0.3.7-1sarge3 | DSA-1503-1 |
| Debian 3.1 | i2c | 1:2.9.1-1sarge2 | DSA-1503-1 |
| Debian 3.1 | kernel-image-2.4.27-arm +1 | 2.4.27-2sarge6 | DSA-1503-1 |
| Debian 3.1 | kernel-image-2.4.27-m68k | 2.4.27-3sarge6 | DSA-1503-1 |
| Debian 3.1 | kernel-image-2.4.27-sparc | 2.4.27-9sarge6 | DSA-1503-1 |
| Debian 3.1 | kernel-image-speakup-i386 | 2.4.27-1.1sarge5 | DSA-1503-1 |
| Debian 3.1 | kernel-latest-2.4-alpha | 101sarge3 | DSA-1503-1 |
| Debian 3.1 | kernel-latest-2.4-i386 | 101sarge2 | DSA-1503-1 |
| Debian 3.1 | kernel-latest-2.4-s390 | 2.4.27-1sarge2 | DSA-1503-1 |
| Debian 3.1 | kernel-latest-2.4-sparc | 42sarge3 | DSA-1503-1 |
| Debian 3.1 | kernel-patch-2.4.27-mips | 2.4.27-10.sarge4.040815-3 | DSA-1503-1 |
| Debian 3.1 | kernel-source-2.4.27 +4 | 2.4.27-10sarge6 | DSA-1503-2, DSA-1503-1 |
| Debian 3.1 | kernel-source-2.6.8 | 2.6.8-16sarge7 | DSA-1304-1 |
| Debian 3.1 | mindi-kernel | 2.4.27-2sarge5 | DSA-1503-1 |
| Debian 3.1 | pcmcia-modules-2.4.27-i386 | 3.2.5+2sarge2 | DSA-1503-1 |
| Debian 3.1 | systemimager | 3.2.3-6sarge5 | DSA-1503-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | kernel +10 | 2.6.18-8.1.4.el5 | RHSA-2007:0347 |
| RHEL 4 | kernel +10 | 2.6.9-55.EL | RHBA-2007:0304 |
| RHEL 3 | kernel +8 | 2.4.21-50.EL | RHSA-2007:0436 |
| RHEL 2 | kernel +8 | 2.4.9-e.72 | RHSA-2007:0673, RHSA-2007:0672 |
Advisories 9
- RHSA-2007:0672 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2007:0347 Red Hat Security Advisory: kernel security and bug fix update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHSA-2007:0436 Red Hat Security Advisory: Updated kernel packages for Red Hat Enterprise Linux 3 Update 9 Red Hat Security Advisories (RHSA) · Jun 26, 2026
- RHBA-2007:0304 Red Hat Bug Fix Advisory: Updated kernel packages available for Red Hat Enterprise Linux 4 Update 5 Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1503-2 kernel-source-2.4.27 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1503-1 kernelimage-2.4.27 - several issues Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1286-1 linux-2.6 Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1304-1 kernel-source-2.6.8 - several Debian Security (DSA / DLA) · Mar 9, 2026
- RHSA-2007:0673 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
References
- RHSA-2007:0436 vendor-advisory
- DSA-1286 vendor-advisory
- RHSA-2007:0347 vendor-advisory
- [linux-netdev] 20070316 [PATCH 2.6.21-rc3] IPV6: ipv6_fl_socklist is inadvertently shared. mailing-list
- USN-464-1 vendor-advisory
- SUSE-SA:2007:043 vendor-advisory
- MDKSA-2007:078 vendor-advisory
- RHSA-2007:0673 vendor-advisory
- 24777 third-party-advisory
- 23104 vdb-entry
- 27528 third-party-advisory
- 26379 third-party-advisory
- 25226 third-party-advisory
- SUSE-SA:2007:029 vendor-advisory
- 24618 third-party-advisory
- 25683 third-party-advisory
- ADV-2007-1084 vdb-entry
- MDVSA-2011:051 vendor-advisory
- 25288 third-party-advisory
- http://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=233478
- RHSA-2007:0672 vendor-advisory
- RHBA-2007-0304 vendor-advisory
- 25099 third-party-advisory
- 25961 third-party-advisory
- DSA-1503 vendor-advisory
- 25078 third-party-advisory
- 25392 third-party-advisory
- http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.20.4
- SUSE-SA:2007:030 vendor-advisory
- 29058 third-party-advisory
- DSA-1304 vendor-advisory
- 25630 third-party-advisory
- 25714 third-party-advisory
- kernel-tcpv6synrecvsoc-dos(33176) vdb-entry
- SUSE-SA:2007:035 vendor-advisory
- oval:org.mitre.oval:def:10130 vdb-entry signature
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=d35690beda1429544d46c8eb34b2e3a8c37ab299
- http://support.avaya.com/elmodocs2/security/ASA-2007-404.htm