CVE-2026-128885
Dbus: stack out-of-bounds write in dbus _dbus_poll() select() fallback when file descriptor exceeds fd_setsize
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).
Fixes and workarounds
Workaround
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.
Source: CNA: redhatAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| Red Hat Enterprise Linux 10 Red Hat dbus
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unknown |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 5.5 medium |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H | CNA: redhat |
Exploit evidence
- https://bugzilla.redhat.com/show_bug.cgi?id=2462795
exploit · ADP: CISA-ADP
References
- https://access.redhat.com/security/cve/CVE-2026-128885CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2462795CNA: redhat · issue-tracking, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2462795ADP: CISA-ADP · exploit
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