Description
The __clear_user function in arch/arm64/lib/clear_user.S in the Linux kernel before 3.17.4 on the ARM64 platform allows local users to cause a denial of service (system crash) by reading one byte beyond a /dev/zero page boundary.
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-ckt2-1 | — |
| Debian 13 | linux | 3.16.7-ckt2-1 | — |
| Debian 12 | linux | 3.16.7-ckt2-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | linux | 3.13.0-44.73 | USN-2466-1 |
| Ubuntu 14.04 LTS | linux-lts-utopic | 3.16.0-29.39~14.04.1 | USN-2467-1 |
Advisories 2
- USN-2466-1 linux vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-2467-1 linux-lts-utopic vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
References
- [oss-security] 20141113 CVE-2014-7843 Linux kernel: aarch64: copying from /dev/zero causes local DoS mailing-list
- https://github.com/torvalds/linux/commit/97fc15436b36ee3956efad83e22a557991f7d19d
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=97fc15436b36ee3956efad83e22a557991f7d19d
- https://bugzilla.redhat.com/show_bug.cgi?id=1163744
- 71082 vdb-entry
- http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.17.4
- 62305 third-party-advisory