CVE-2015-1853
chrony before 1.31.1 does not properly protect state variables in authenticated symmetric NTP associations, which allows remote attackers with knowledge of NTP peering to cause a denial of service (inability to synchronize) via random timestamps in…
Does this matter?
Lower severity and a low EPSS score (1.70%). Track it; it rarely justifies an emergency change on its own.
Description
chrony before 1.31.1 does not properly protect state variables in authenticated symmetric NTP associations, which allows remote attackers with knowledge of NTP peering to cause a denial of service (inability to synchronize) via random timestamps in crafted NTP data packets.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.70% probability · 77th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- tuxfamily/chrony
- Source
- secalert@redhat.com
EPSS 1.7% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://chrony.tuxfamily.org/News.htmlRelease Notes, Vendor Advisory
- https://security.gentoo.org/glsa/201507-01Third Party Advisory
- http://chrony.tuxfamily.org/News.htmlRelease Notes, Vendor Advisory
- https://security.gentoo.org/glsa/201507-01Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.