CVE-2015-3405 Weak cryptography in n/a

What is CVE-2015-3405?

CVE-2015-3405 is a high-severity vulnerability in Debian Debian Linux, published on 9 Aug 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

ntp-keygen in ntp 4.2.8px before 4.2.8p2-RC2 and 4.3.x before 4.3.12 does not generate MD5 keys with sufficient entropy on big endian machines when the lowest order byte of the temp variable is between 0x20 and 0x7f and not #, which might allow remote attackers to obtain the value of generated MD5 keys via a brute force attack with the 93 possible keys.

Weakness: CWE-331

Which versions are affected by CVE-2015-3405?

It affects 13 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Ntp Ntp, Opensuse Suse Linux Enterprise Server, Opensuse Project Suse Linux Enterprise Desktop, Redhat Enterprise Linux Desktop and 7 more.

How do I fix CVE-2015-3405?

Upgrade to a fixed version.

Is CVE-2015-3405 being exploited?

There is no known exploitation of CVE-2015-3405 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-2015-3405, GHSA-wwx9-mwhp-g8mc, UBUNTU-CVE-2015-3405.