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TI-2015-01638 Aliases CVE-2015-1821GHSA-cm73-xw9w-xqmm

Heap-based buffer overflow in chrony before 1.31.1 allows remote authenticated users to…

Priority LOW 35CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
— Not recorded in CVSS 2.0
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
Partial · Partial · Partial
Fix status
Fixed

Attack profile from CVSS 2.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-119 and the CVSS impact.

Summary

Heap-based buffer overflow in chrony before 1.31.1 allows remote authenticated users to cause a denial of service (chronyd crash) or possibly execute arbitrary code by configuring the (1) NTP or (2) cmdmon access with a subnet size that is indivisible by four and an address with a nonzero bit in the subnet remainder.

Why it matters now

EPSS 0.03414 88th percentileScored 2026-11-07
Fix Fixed Red Hat: 1 advisory

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:tuxfamily:chrony:*:*:*:*:*:*:*:*up to 1.31VulnerableTuxfamily
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*7.0VulnerableDebian
  • cpe:2.3:a:tuxfamily:chrony:*:*:*:*:*:*:*:* Versions up to 1.31 Vulnerable ·Tuxfamily
  • cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Debian

Remediation

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-2015-1821
  2. 2026-10-03 Alias added: GHSA-cm73-xw9w-xqmm

References

Patch 1

Advisory 2

Other 1

Sources

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