Read the docs
TI-2015-01664 Aliases CVE-2015-1853GHSA-gf8j-j7q8-vhh5

chrony before 1.31.1 does not properly protect state variables in authenticated symmetric…

Priority LOW 32Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

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.

Why it matters now

EPSS 0.01696 77th percentileScored 2026-11-07
Fix Fixed chrony (chrony): 1.31.1Red Hat: 1 advisory

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
chronychronybefore 1.31.11.31.1Patch availableCNA
  • chrony Vendorchrony Affected before 1.31.1 Fixed in 1.31.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:tuxfamily:chrony:*:*:*:*:*:*:*:*before 1.31.1VulnerableTuxfamily
  • cpe:2.3:a:tuxfamily:chrony:*:*:*:*:*:*:*:* Versions before 1.31.1 Vulnerable ·Tuxfamily

Remediation

  • Fix · CNA chrony (chrony) Fixed in 1.31.1

Red Hat 1 advisory

  • RHSA-2015:2241 Released 2015-11-19 · Red Hat rating Moderate
    chrony security, bug fix, and enhancement update
    • Red Hat Enterprise Linux Client (v. 7) chrony-2.1.1-1.el7
    • Red Hat Enterprise Linux ComputeNode (v. 7) chrony-2.1.1-1.el7
    • Red Hat Enterprise Linux Server (v. 7) chrony-2.1.1-1.el7
    • Red Hat Enterprise Linux Workstation (v. 7) chrony-2.1.1-1.el7

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2015:2241
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed RHSA-2015:2241
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2015:2241
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2015:2241

Timeline

  1. 2026-10-02 Threatist record created from CVE-2015-1853
  2. 2026-10-03 Alias added: GHSA-gf8j-j7q8-vhh5

References

Advisory 2

  • TI-2016-01428 chrony before 1.31.2 and 2.x before 2.2.1 do not verify peer associations of symmetric… CVSS 3.0HIGH 8.1
  • TI-2015-01638 Heap-based buffer overflow in chrony before 1.31.1 allows remote authenticated users to… CVSS 2.0MEDIUM 6.5
  • TI-2015-01639 chrony before 1.31.1 does not initialize the last "next" pointer when saving… CVSS 2.0MEDIUM 6.5
  • TI-2012-03844 Multiple integer overflows in pktlength.c in Chrony before 1.29 allow remote attackers to… CVSS 2.0MEDIUM 5.0
  • TI-2012-03845 cmdmon.c in Chrony before 1.29 allows remote attackers to obtain potentially sensitive… CVSS 2.0MEDIUM 5.0
  • TI-2010-00281 chronyd in Chrony before 1.23.1, and possibly 1.24-pre1, generates a syslog message for… CVSS 2.0MEDIUM 5.0
See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences