Dbus: stack out-of-bounds write in dbus _dbus_poll() select() fallback when file descriptor exceeds fd_setsize
Summary
| CVE | CVE-2026-128885 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-11-13 21:17:45 UTC |
| Updated | 2026-11-13 22:17:23 UTC |
| Description | A flaw was found in D-Bus. In configurations where the daemon falls back to using the Unix select() mechanism for event monitoring, it does not verify whether file descriptor numbers exceed allocated limits. A local attacker can exploit this flaw by opening a large number of concurrent connections to trigger an out-of-bounds write on the stack. This can cause the daemon to crash, resulting in a Denial of Service (DoS). |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Problem Types: CWE-121 | CWE-121 Stack-based Buffer Overflow
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/security/cve/CVE-2026-128885 | [email protected] | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | bugzilla.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-04-26T20:06:04.000Z | Reported to Red Hat. |
| CNA | 2026-08-19T16:20:17.572Z | Made public. |
Workarounds
CNA: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
There are currently no legacy QID mappings associated with this CVE.