CVE-2015-7974 Auth bypass in n/a

What is CVE-2015-7974?

CVE-2015-7974 is a high-severity authentication bypass vulnerability in Debian Debian Linux, published on 26 Jan 2016. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

NTP 4.x before 4.2.8p6 and 4.3.x before 4.3.90 do not verify peer associations of symmetric keys when authenticating packets, which might allow remote attackers to conduct impersonation attacks via an arbitrary trusted key, aka a "skeleton key."

Weakness: CWE-287

Which versions are affected by CVE-2015-7974?

It affects 6 products.

Products include Debian Debian Linux, Netapp Clustered Data Ontap, Netapp Oncommand Balance, Ntp Ntp, Siemens Tim 4r-Ie Dnp3 Firmware, Siemens Tim 4r-Ie Firmware.

How do I fix CVE-2015-7974?

Upgrade to a fixed version.

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

Is CVE-2015-7974 being exploited?

There is no known exploitation of CVE-2015-7974 in the wild and no public exploit code.

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-2015-7974, GHSA-26v6-r4x8-vv44, UBUNTU-CVE-2015-7974.