CVE-2015-2721 Weak cryptography in n/a

What is CVE-2015-2721?

CVE-2015-2721 is a medium-severity vulnerability in Canonical Ubuntu Linux, published on 6 Jul 2015. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Mozilla Network Security Services (NSS) before 3.19, as used in Mozilla Firefox before 39.0, Firefox ESR 31.x before 31.8 and 38.x before 38.1, Thunderbird before 38.1, and other products, does not properly determine state transitions for the TLS state machine, which allows man-in-the-middle attackers to defeat cryptographic protection mechanisms by blocking messages, as demonstrated by removing a forward-secrecy property by blocking a ServerKeyExchange message, aka a "SMACK SKIP-TLS" issue.

Weakness: CWE-310

Which versions are affected by CVE-2015-2721?

It affects 8 products.

Products include Canonical Ubuntu Linux, Debian Debian Linux, Mozilla Network Security Services, Novell Suse Linux Enterprise Desktop, Novell Suse Linux Enterprise Server, Novell Suse Linux Enterprise Software Development Kit and 2 more.

How do I fix CVE-2015-2721?

Upgrade to a fixed version.

Is CVE-2015-2721 being exploited?

There is no known exploitation of CVE-2015-2721 in the wild and no public exploit code.

Other vulnerabilities in Canonical Ubuntu Linux

• CVE-2020-11651 SaltStack Salt Authentication Bypass Exploited Critical 9.8
• CVE-2020-7247 OpenSMTPD Remote Code Execution Exploited Critical 9.8
• CVE-2019-16928 Exim Out-of-bounds Write Exploited Critical 9.8
• CVE-2018-6789 Exim Buffer Overflow Exploited Critical 9.8
• CVE-2015-2590 Oracle Java SE and Java SE Embedded Remote Code Execution Exploited Critical 9.8

All Canonical Ubuntu Linux vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2015-2721, GHSA-fhwj-6xh8-h4rw, UBUNTU-CVE-2015-2721.