Description
chrony before 1.31.2 and 2.x before 2.2.1 do not verify peer associations of symmetric keys when authenticating packets, which might allow remote attackers to conduct impersonation attacks via an arbitrary trusted key, aka a "skeleton key."
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 ↗Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | chrony | 2.1.1-1ubuntu0.1 | — |
| Ubuntu 14.04 LTS | chrony | 1.29-1ubuntu0.1 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | chrony | 2.4.1-1.1 | openSUSE-SU-2024:10345-1 |
Advisories 3
- DLA-742-1 chrony - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-414-1 chrony - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10345-1 chrony-2.4.1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026