Advisory Details

July 19th, 2021

(Pwn2Own) Microsoft Exchange Server CabUtility ExtractCab Directory Traversal Remote Code Execution Vulnerability

CVE ID	CVE-2021-31206
CVSS SCORE	7.1, AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
AFFECTED VENDORS	Microsoft
AFFECTED PRODUCTS	Exchange
VULNERABILITY DETAILS	This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of Microsoft Exchange Server. User interaction is required to exploit this vulnerability. The specific flaw exists within the parsing of CAB files. When handling filenames specified within a CAB file, the process does not properly validate a user-supplied path prior to using it in file operations. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of SYSTEM.
ADDITIONAL DETAILS	Microsoft has issued an update to correct this vulnerability. More details can be found at: https://msrc.microsoft.com/update-guide/en-us/vulnerability/CVE-2021-31206
DISCLOSURE TIMELINE	2021-04-08 - Vulnerability reported to vendor 2021-07-19 - Coordinated public release of advisory
CREDIT	Steven Seeley (mr_me) of Source Incite

BACK TO ADVISORIES