Description
The evm_verify_hmac function in security/integrity/evm/evm_main.c in the Linux kernel before 4.5 does not properly copy data, which makes it easier for local users to forge MAC values via a timing side-channel attack.
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 | 4.4.2-1 | — |
| Debian 13 | linux | 4.4.2-1 | — |
| Debian 12 | linux | 4.4.2-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | linux | 3.13.0-85.129 | USN-2946-1 |
| Ubuntu 14.04 LTS | linux-lts-utopic | 3.16.0-69.89~14.04.1 | USN-2948-1 |
| Ubuntu 14.04 LTS | linux-lts-vivid | 3.19.0-58.64~14.04.1 | USN-2949-1 |
| Ubuntu 14.04 LTS | linux-lts-wily | 4.2.0-35.40~14.04.1 | USN-2947-2 |
Advisories 4
- USN-2946-1 linux vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-2947-2 linux-lts-wily vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-2948-1 linux-lts-utopic vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-2949-1 linux-lts-vivid vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
References
- USN-2949-1 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1324867
- https://security-tracker.debian.org/tracker/CVE-2016-2085
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=613317bd212c585c20796c10afe5daaa95d4b0a1
- USN-2947-3 vendor-advisory
- USN-2947-2 vendor-advisory
- https://people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-2085.html
- USN-2947-1 vendor-advisory
- USN-2946-2 vendor-advisory
- https://github.com/torvalds/linux/commit/613317bd212c585c20796c10afe5daaa95d4b0a1
- USN-2948-1 vendor-advisory
- USN-2946-1 vendor-advisory
- USN-2948-2 vendor-advisory