Description
arch/x86/entry/entry_64.S in the Linux kernel before 4.1.6 on the x86_64 platform does not properly determine when nested NMI processing is occurring, which allows local users to cause a denial of service (skipped NMI) by modifying the rsp register, issuing a syscall instruction, and triggering an NMI.
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 | 4.0.8-2 | — |
| Debian 13 | linux | 4.0.8-2 | — |
| Debian 12 | linux | 4.0.8-2 | — |
| Debian 8 | linux | 3.16.7-ckt11-1+deb8u2 | DSA-3313-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | linux | 3.13.0-59.98 | USN-2700-1, USN-2688-1 |
| Ubuntu 14.04 LTS | linux-lts-utopic | 3.16.0-45.60~14.04.1 | USN-2689-1 |
| Ubuntu 14.04 LTS | linux-lts-vivid | 3.19.0-25.26~14.04.1 | USN-2690-1 |
Advisories 5
- USN-2700-1 linux vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-2688-1 linux vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-3313-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-2689-1 linux-lts-utopic vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-2690-1 linux-lts-vivid vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1243489
- 76003 vdb-entry
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=810bc075f78ff2c221536eb3008eac6a492dba2d
- https://github.com/torvalds/linux/commit/810bc075f78ff2c221536eb3008eac6a492dba2d
- USN-2689-1 vendor-advisory
- USN-2690-1 vendor-advisory
- USN-2691-1 vendor-advisory
- USN-2688-1 vendor-advisory
- DSA-3313 vendor-advisory
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.1.6
- [oss-security] 20150722 Linux x86_64 NMI security issues mailing-list
- USN-2687-1 vendor-advisory