A flaw has been found in Artifex MuPDF up to 1.26.1 on Windows. The impacted element is the function get_system_dpi of the file platform/x11/win_main.c. This manipulation causes uncontrolled search path. The attack requires local access. The attack is considered to have high complexity. The exploitability is regarded as difficult. Upgrading to version 1.26.2 is sufficient to resolve this issue. Patch name: ebb125334eb007d64e579204af3c264aadf2e244. Upgrading the affected component is recommended.

MuPDF versions 1.23.0 through 1.27.0 contain a double-free vulnerability in fz_fill_pixmap_from_display_list() when an exception occurs during display list rendering. The function accepts a caller-owned fz_pixmap pointer but incorrectly drops the pixmap in its error handling path before rethrowing the exception. Callers (including the barcode decoding path in fz_decode_barcode_from_display_list) also drop the same pixmap in cleanup, resulting in a double-free that can corrupt the heap and crash the process. This issue affects applications that enable and use MuPDF barcode decoding and can be triggered by processing crafted input that causes a rendering-time error while decoding barcodes.

An exploitable heap out of bounds write vulnerability exists in the Fitz graphical library part of the MuPDF renderer. A specially crafted PDF file can cause a out of bounds write resulting in heap metadata and sensitive process memory corruption leading to potential code execution. Victim needs to open the specially crafted file in a vulnerable reader in order to trigger this vulnerability.

An exploitable memory corruption vulnerability exists in the JBIG2 parser of Artifex MuPDF 1.9. A specially crafted PDF can cause a negative number to be passed to a memset resulting in memory corruption and potential code execution. An attacker can specially craft a PDF and send to the victim to trigger this vulnerability.