Atril Document Viewer is the default document reader of the MATE desktop environment for Linux

Overview

Atril Document Viewer is the default document reader of the MATE desktop environment for Linux. A single-click remote code execution vulnerability in versions prior to 1.26.3 and 1.28.4 allows an attacker to achieve arbitrary code execution as the user by tricking them into clicking a link inside a malicious PDF document. The PDF can be packaged as a polyglot file that is simultaneously a valid PDF and a valid ELF shared library, making the attack a single-file, single-click, configuration-independent RCE on stock atril installations. The root cause is shell/ev-application.c:ev_spawn, which builds a command line from attacker-controlled PDF link-destination fields without applying g_shell_quote. The cmdline is then handed to g_app_info_create_from_commandline, which shell-parses it back into argv — splitting any embedded --gtk-module=PATH into a separate argv element. GTK then dlopen()s the path during init, running any __attribute__((constructor)) it finds. Versions 1.26.3 and 1.28.4 contain a patch for the issue. This is the same defect class as CVE-2023-51698 (CBT --checkpoint-action injection in comics-document.c, fixed in 1.6.2) but in a different code path (shell/ev-application.c) that the original patch did not touch.

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.