CVE-2021-31509

Vulnerability

A write past the end of an allocated buffer exists in the parsing of DXF files within OpenText Brava! Desktop version 16.6.3.84. The flaw is triggered when the application processes a specially crafted DXF file without properly validating user-supplied data. User interaction is required, as the target must visit a malicious page or open a malicious file [1].

Exploitation

An attacker can exploit this vulnerability remotely by luring a user to open a crafted DXF file or visit a malicious web page that invokes Brava! Desktop. No authentication or special network position is needed; the attacker relies on social engineering to trigger the parsing code path. Once the malformed DXF is processed, the insufficient bounds checking allows an out-of-bounds write [1].

Impact

Successful exploitation allows an attacker to execute arbitrary code in the context of the current user process. This results in a complete compromise of confidentiality, integrity, and availability (CVSS 7.8, vector AV:L/PR:N/UI:R/S:U/C:H/I:H/A:H). The attacker gains the same privileges as the logged-on user [1].

Mitigation

At the time of publication (June 2021), no vendor patch or workaround was publicly disclosed in the available references. The vulnerability is known under ZDI-CAN-13309 and is not listed on CISA's Known Exploited Vulnerabilities (KEV) catalog as of the advisory date. Users should monitor OpenText for updates or consider restricting access to untrusted DXF files [1].