CVE-2019-13257

Vulnerability

XnView Classic version 2.48 contains a user mode write access violation (AV) starting at address xnview+0x00000000003273aa. The crash occurs when opening a specially crafted file, as demonstrated in the provided debug output [1]. The exact file format and conditions required are not specified, but the vulnerability is triggered by user interaction (opening a file).

Exploitation

An attacker can exploit this vulnerability by crafting a malicious file that triggers the write AV when opened in XnView Classic 2.48. The attacker must convince the user to open the file, e.g., via social engineering. No authentication or special privileges are required; the user only needs to double-click or open the file in the application.

Impact

Successful exploitation results in a user mode write access violation, which typically causes the application to crash (denial of service). Depending on the nature of the write AV, it may potentially be leveraged for arbitrary code execution, but the available reference only confirms a crash [1].

Mitigation

As of the publication date (2019-07-04), no official patch or fixed version has been released for XnView Classic 2.48. Users should avoid opening untrusted files with the application and monitor vendor updates for a fix.