CVE-2015-7691 Denial of service in n/a

What is CVE-2015-7691?

CVE-2015-7691 is a high-severity denial of service 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

The crypto_xmit 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 (crash) via crafted packets containing particular autokey operations. NOTE: This vulnerability exists due to an incomplete fix for CVE-2014-9750.

Weakness: CWE-20

Which versions are affected by CVE-2015-7691?

It affects 13 products.

Products include Debian Debian Linux, Netapp Clustered Data Ontap, Netapp Data Ontap, Netapp Oncommand Performance Manager, Netapp Oncommand Unified Manager, Ntp Ntp and 7 more.

How do I fix CVE-2015-7691?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2015-7691 being exploited?

There is no known exploitation of CVE-2015-7691 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-2015-7691, GHSA-2cm3-5rf2-6c3w, UBUNTU-CVE-2015-7691.