CVE-2015-1853

Publication date 9 December 2019

Last updated 25 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.5 · Medium

Score breakdown

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.

From the Ubuntu Security Team

Miroslav Lichvár discovered a head-based buffer overflow in chrony. A remote attacker could use this vulnerability to cause a denial of service (crash) or execute arbitrary code.

Status

Package Ubuntu Release Status
chrony 18.10 cosmic
Not affected
18.04 LTS bionic
Not affected
17.10 artful
Not affected
17.04 zesty Ignored end of life
16.10 yakkety Ignored end of life
16.04 LTS xenial
Not affected
15.10 wily Ignored end of life
15.04 vivid Ignored end of life
14.10 utopic Ignored end of life
14.04 LTS trusty
Fixed 1.29-1ubuntu0.1
12.04 LTS precise Ignored end of life
10.04 LTS lucid Ignored end of life

Severity score breakdown

Parameter Value
Base score 6.5 · Medium
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

Other references

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