CVE-2015-7853

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 11.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-08-07 · updated 2026-06-17
Weakness: CWE-120

Description

The datalen parameter in the refclock driver in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to execute arbitrary code or cause a denial of service (crash) via a negative input value.

Affected products

Clustered Data ONTAP: all versions
NetApp Data ONTAP operating in 7-Mode: all versions
NetApp Oncommand Balance: all versions
NetApp Oncommand Performance Manager: all versions
NetApp OnCommand Unified Manager for 7-Mode (core package): all versions
NTP: from 4.2.0 before 4.2.8; from 4.3.0 before 4.3.77; 4.2.8, 4.2.8-p1, 4.2.8-p1-beta1, 4.2.8-p1-beta2, 4.2.8-p1-beta3, 4.2.8-p1-beta4 (+11) — fixed in 4.2.8, 4.3.77

How to fix

Upgrade to a fixed version: NTP 4.2.8, 4.3.77. Check the vendor advisory for mitigations.

References

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