Vulnerability-Lookup

CVE-2026-16730 (GCVE-0-2026-16730)

Vulnerability from cvelistv5 – Published: 2026-07-24 11:26 – Updated: 2026-07-24 14:48

Title

Dbus-broker: dbus-broker: session bus denial of service via emfile during peer setup

Summary

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.

Severity

5.5 (Medium)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-755 - Improper Handling of Exceptional Conditions

Assigner

redhat

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-16730	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2506348	issue-trackingx_refsource_REDHAT
https://github.com/bus1/dbus-broker/issues/435

Impacted products

4 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9
Red Hat	Red Hat Hardened Images	cpe:/a:redhat:hummingbird:1
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public

2026-07-23 00:00

Credits

Red Hat would like to thank Josh Simmons for reporting this issue.

Show details on NVD website

JSON

To clipboard

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GHSA-77QF-9J4M-PH58

Vulnerability from github – Published: 2026-07-24 12:30 – Updated: 2026-07-24 12:30

Details

Severity

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

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  "affected": [],
  "aliases": [
    "CVE-2026-16730"
  ],
  "database_specific": {
    "cwe_ids": [
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-24T12:16:47Z",
    "severity": "MODERATE"
  },
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  "id": "GHSA-77qf-9j4m-ph58",
  "modified": "2026-07-24T12:30:53Z",
  "published": "2026-07-24T12:30:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-16730"
    },
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      "url": "https://github.com/bus1/dbus-broker/issues/435"
    },
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      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

CVE-2026-16730 (GCVE-0-2026-16730)

GHSA-77QF-9J4M-PH58

Tags

Sightings

Nomenclature