FFmpeg adx_write_trailer Divide-by-Zero Vulnerability [CVE-2019-13390]

CVE Number – CVE-2019-13390

A vulnerability in FFmpeg could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on a targeted system.The vulnerability is due to a divide-by-zero condition in the adx_write_trailer function, as defined in the libavformat/rawenc.c source code file of the affected software. An attacker could exploit this vulnerability by persuading a user to access a crafted file on the targeted system. A successful exploit could cause the affected software to crash, resulting in a DoS condition.Proof-of-concept (PoC) code that demonstrates an exploit of this vulnerability is publicly available.FFmpeg has confirmed this vulnerability; however, software updates are not available.

Analysis

• To exploit this vulnerability, the attacker may use misleading language or instructions to persuade a user to access a file that submits malicious input to the affected software.

Safeguards

• Administrators are advised to contact the vendor regarding future updates and releases.
  
  Administrators are advised to allow only trusted users to have network access.
  
  Administrators are advised to use an unprivileged account when browsing the Internet.
  
  Administrators are advised to monitor critical systems.
  
  Users are advised not to open email messages from suspicious or unrecognized sources. If users cannot verify that links or attachments included in email messages are safe, they are advised not to open them.
  
  Users are advised not to visit websites or follow links that have suspicious characteristics or cannot be verified as safe.

Vendor Announcements

• FFmpeg has released a bug report at the following link: Division by zero bug from libavformat/rawenc.c:70:50

Fixed Software

• At the time this alert was first published, the vendor had not released a software update.