SB2021092020 - Multiple vulnerabilities in ytnef 



SB2021092020 - Multiple vulnerabilities in ytnef

Published: September 20, 2021

Security Bulletin ID SB2021092020
Severity
High
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Double Free (CVE-ID: CVE-2021-3403)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a double free error within the TNEFSubjectHandler() function in lib/ytnef.c. A remote attacker can trick the victim to open a specially crafted file, trigger a double free error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.


2) Heap-based buffer overflow (CVE-ID: CVE-2021-3404)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error within the SwapWord() function in lib/ytnef.c. A remote attacker can trick the victim to open a specially crafted file, trigger a heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.


Remediation

Install update from vendor's website.