CVE-2026-16730
Dbus-broker: dbus-broker: session bus denial of service via emfile during peer setup
Description
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.
INFO
Published Date :
July 24, 2026, 12:16 p.m.
Last Modified :
July 24, 2026, 12:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-16730
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 53f830b8-0a3f-465b-8143-3b8a9948e749 | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Increase the process file descriptor limit.
- Modify error handling for SO_PEERPIDFD.
- Update dbus-broker to handle resource limits gracefully.
- Limit concurrent connections to the D-Bus session bus.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-16730.
| URL | Resource |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-16730 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2506348 | |
| https://github.com/bus1/dbus-broker/issues/435 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-16730 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-16730
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-16730 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-16730 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'packageName': 'dbus-broker', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'packageName': 'dbus-broker', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:hummingbird:1'], 'vendor': 'Red Hat', 'product': 'Red Hat Hardened Images', 'packageName': 'dbus-broker', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:openshift:4'], 'vendor': 'Red Hat', 'product': 'Red Hat OpenShift Container Platform 4', 'packageName': 'rhcos', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'unknown'}] Added Description 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. Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-755 Added Reference https://access.redhat.com/security/cve/CVE-2026-16730 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2506348 Added Reference https://github.com/bus1/dbus-broker/issues/435