CVE-2021-31507

Vulnerability

This vulnerability resides in the CGM file parsing component of OpenText Brava! Desktop version 16.6.3.84. The flaw is a stack-based buffer overflow caused by improper validation of the length of user-supplied data before copying it to a stack buffer. An attacker must convince a user to open a malicious CGM file or visit a crafted page that triggers parsing. [1]

Exploitation

Exploitation requires user interaction: the target must open a specially crafted CGM file or navigate to a malicious web page that loads the file into Brava! Desktop. The attacker does not need prior authentication or local access; the attack vector is remote, leveraging the user's action to trigger the overflow. [1]

Impact

Successful exploitation allows the attacker to execute arbitrary code in the context of the current process. Given the CVSS score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), the impact includes full compromise of confidentiality, integrity, and availability of the affected system. [1]

Mitigation

As of the publication date (2021-06-29), a vendor-supplied patch has not been publicly detailed in the reference. OpenText customers should consult the vendor's advisory for fixed version information. Until a patch is applied, avoid opening untrusted CGM files or visiting untrusted web pages that may load such files. [1]