# CVE-2026-16730: dbus-broker denial of service via file-descriptor exhaustion

Source: https://junglewise.ai/threats/cve-2026-16730-dbus-broker-denial-of-service-via-file-descriptor-exhaustion  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-24. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2026-16730 · Severity: medium · CVSS 5.5 · Published 2026-07-24

A vulnerability in dbus-broker, a core component used for communication between applications on Linux systems, allows a local user to crash the entire desktop session. By opening a large number of connections to the system's message bus, an attacker can exhaust available resources and force the broker to shut down. This results in a denial of service where the user is effectively logged out and active applications may fail.

Technologies: [Red Hat Enterprise Linux 10](https://junglewise.ai/threats/technologies/enterprise-linux-10), [Red Hat Enterprise Linux 9](https://junglewise.ai/threats/technologies/enterprise-linux-9). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-16730 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-16730 being exploited in the wild.

**How severe is CVE-2026-16730?** Medium severity, with a CVSS score of 5.5, published 24 July 2026.

**Which products and versions are affected?** Bus1 Dbus-Broker Up to 37; Red Hat Enterprise Linux 10 All versions; Red Hat Enterprise Linux 9 All versions.

**Is there a fix for CVE-2026-16730?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-16730 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-16730?** Check whether you run Bus1 Dbus-Broker, Red Hat Enterprise Linux 10 or Red Hat Enterprise Linux 9 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A flaw exists in dbus-broker's handling of exceptional conditions during peer connection setup. When the process reaches its file-descriptor limit, system calls such as getsockopt(SO_PEERPIDFD) return EMFILE or ENFILE errors. Instead of gracefully refusing the new connection, dbus-broker treats these as fatal errors and exits. A local attacker, including one within a Flatpak sandbox, can exploit this by opening numerous connections to the user session bus to trigger the crash. This results in a complete denial of service for the affected user's desktop session.

## Affected products

- Red Hat Red Hat Enterprise Linux 9 All versions
- Red Hat Red Hat Enterprise Linux 10 All versions
- bus1 dbus-broker Up to 37

## Timeline

- 2026-05-14: other: Issue first reported on GitHub
- 2026-07-23: disclosed: Bug reported to Red Hat Bugzilla
- 2026-07-24: advisory: CVE published to NVD

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-16730](https://access.redhat.com/security/cve/CVE-2026-16730)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2506348](https://bugzilla.redhat.com/show_bug.cgi?id=2506348)
- [https://github.com/bus1/dbus-broker/issues/435](https://github.com/bus1/dbus-broker/issues/435)

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