CVE-2015-7855

CVE-2015-7855 is a medium-severity vulnerability in Ntp with a CVSS 3.x base score of 6.5. Its EPSS exploit-prediction score of 31% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Description

The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (assertion failure) via a 6 or mode 7 packet containing a long data value.

Frequently asked questions

What is CVE-2015-7855?
The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (assertion failure) via a 6 or mode 7 packet containing a long data value.
How severe is CVE-2015-7855?
CVE-2015-7855 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2015-7855 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-7855?
CVE-2015-7855 primarily affects Ntp. In total, 28 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-7855?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-7855 published?
CVE-2015-7855 was published on 2017-08-07 and last updated on 2026-06-17.

References

Affected products (28)

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Threat intelligence

Threat-intel indicators referencing this CVE: