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Case File

CVE-2015-2721

MEDIUM · CVSS 4.3 EPSS 3.28%

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2015-07-06 · Last synced 2026-08-04

CyberRota Analysis

This is a medium severity vulnerability with a CVSS score of 4.3. It affects Exchange, Firefox.

CVE
CVE-2015-2721
Severity
MEDIUM
CVSS
4.3
EPSS
3.28%
Exchange Firefox

Original NVD 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.