dbus-broker DoS via FD exhaustion causing fatal broker exit
CVE-2026-16730 Published on July 24, 2026
Dbus-broker: dbus-broker: session bus denial of service via emfile during peer setup
A flaw was found in dbus-broker. When the process file-descriptor limit is reached, EMFILE/ENFILE errors during peer setup (notably SO_PEERPIDFD) are handled as fatal failures, causing the broker to exit. A local attacker who can open many connections to the user session bus can trigger this and deny service to the desktop session. Flatpak applications can reach the host session bus through the dbus proxy.
Vulnerability Analysis
CVE-2026-16730 is exploitable with local system access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Timeline
Reported to Red Hat.
Made public. 58 days later.
Weakness Type
Improper Handling of Exceptional Conditions
The software does not handle or incorrectly handles an exceptional condition.
Products Associated with CVE-2026-16730
Want to know whenever a new CVE is published for Red Hat products? stack.watch will email you.
