CVE-2015-7871 Auth bypass in n/a

What is CVE-2015-7871?

CVE-2015-7871 is a critical authentication bypass vulnerability in Debian Debian Linux, published on 7 Aug 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Crypto-NAK packets in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to bypass authentication.

Weakness: CWE-287

Which versions are affected by CVE-2015-7871?

It affects 7 products.

Products include Debian Debian Linux, Netapp Clustered Data Ontap, Netapp Data Ontap, Netapp Oncommand Balance, Netapp Oncommand Performance Manager, Netapp Oncommand Unified Manager and 1 more.

How do I fix CVE-2015-7871?

Upgrade to a fixed version.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2015-7871 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2015-7871 exists.

Public exploit code: 1 Metasploit module.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2015-7871, GHSA-mxc3-mjx4-gjc9, UBUNTU-CVE-2015-7871.