Description
The __switch_to function in arch/x86/kernel/process_64.c in the Linux kernel through 3.18.1 does not ensure that Thread Local Storage (TLS) descriptors are loaded before proceeding with other steps, which makes it easier for local users to bypass the ASLR protection mechanism via a crafted application that reads a TLS base address.
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 | 3.16.7-ckt4-1 | — |
| Debian 13 | linux | 3.16.7-ckt4-1 | — |
| Debian 12 | linux | 3.16.7-ckt4-1 | — |
| Debian 7 | linux | 3.2.65-1+deb7u1 | DSA-3128-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-riscv +6 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +4 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +3 | No fix yet | — |
| Ubuntu 14.04 LTS | linux | 3.13.0-46.75 | USN-2516-1 |
| Ubuntu 14.04 LTS | linux-lts-utopic | 3.16.0-31.41~14.04.1 | USN-2517-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | linux-azure-fde-5.15 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | kernel-rt +7 | 3.10.0-327.rt56.204.el7 | RHSA-2015:2411 |
| RHEL 7 | perf +18 | 3.10.0-327.el7 | RHSA-2015:2152 |
| RHEL 6 | perf +16 | 2.6.32-504.23.4.el6 | RHSA-2015:1081 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 | kernel-docs | 3.12.38-44.5 | SUSE-SU-2015:0529-1 |
| SLES 12 | kernel-ec2 +5 | 3.12.38-44.1 | SUSE-SU-2015:0529-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 | kernel-xen +3 | 3.12.38-44.1 | SUSE-SU-2015:0529-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12_Update_3 | 1-2.2 | SUSE-SU-2015:0529-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | dtrace-modules-3.8.13-68.3.2.el6uek | 0.4.3-4.el6 | ELSA-2015-3041 |
| Oracle Linux 7 | dtrace-modules-3.8.13-68.3.2.el7uek | 0.4.3-4.el7 | ELSA-2015-3041 |
| Oracle Linux 7 | kernel-uek +5 | 3.8.13-68.3.2.el7uek | ELSA-2015-3041 |
| Oracle Linux 7 | perf +11 | 3.10.0-327.el7 | ELSA-2015-2152 |
Advisories 9
- RHSA-2015:2411 Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2015:2152 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2015:1081 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- USN-2516-1 linux vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-3128-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-2517-1 linux-lts-utopic vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2015:0529-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2015-2152 Important: kernel security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Nov 24, 2015
- ELSA-2015-3041 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Jun 10, 2015
References
- FEDORA-2015-0517 vendor-advisory
- USN-2515-1 vendor-advisory
- https://github.com/torvalds/linux/commit/f647d7c155f069c1a068030255c300663516420e
- USN-2542-1 vendor-advisory
- SUSE-SU-2015:0736 vendor-advisory
- USN-2541-1 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1177260
- USN-2518-1 vendor-advisory
- MDVSA-2015:058 vendor-advisory
- FEDORA-2015-0515 vendor-advisory
- 71794 vdb-entry
- SUSE-SU-2015:0529 vendor-advisory
- [oss-security] 20141225 Re: CVE Request: Linux x86_64 userspace address leak mailing-list
- USN-2517-1 vendor-advisory
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=f647d7c155f069c1a068030255c300663516420e
- openSUSE-SU-2015:0714 vendor-advisory
- DSA-3128 vendor-advisory
- USN-2516-1 vendor-advisory
- RHSA-2015:1081 vendor-advisory