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CVE-2026-68155

Last refreshed2026-10-03

Status: UPDATED  |  Advisory ID: CVE-2026-68155

Key Details

CVECVE-2026-68155
CVSS Score / Version7.5 (High) / CVSS v3.1
Updated2026-10-03
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Proseattack vector is network; attack complexity is low; privileges required is none; user interaction is none; scope is unchanged; confidentiality impact is none; integrity impact is none; availability impact is high.
Affected productsLinux Linux

Affected Products, Subsystems & Sectors

VendorProductAffected VersionsPatch Status
LinuxLinux
SubsystemsGeneral OT
SectorsMultiple

What to Know

In the Linux kernel, the following vulnerability has been resolved:

libceph: Reject monmaps advertising zero monitors

A message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a

monitor to the client. This monmap contains information about the

existing monitors in the cluster. Currently, a monmap indicating that

there are zero monitors in the cluster is treated as valid. However, it

is impossible to have zero monitors in the cluster and still receive a

valid monmap from a monitor. Therefore, such a monmap must be corrupted

and should be treated as invalid. Furthermore, a monmap with a monitor

count of zero can subsequently crash the client when attempting to open

a session with a monitor in __open_session(). This happens because the

"BUG_ON(monc->monmap->num_mon < 1)" assertion in pick_new_mon() is

triggered.

This patch extends a check in ceph_monmap_decode() to also reject

arriving mon_maps with num_mon == 0 rather than only with

num_mon > CEPH_MAX_MON.

[ idryomov: drop "log output for unusual values of num_mon" part ] (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References

SourceReference
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2026-68155
CVEhttps://www.cve.org/CVERecord?id=CVE-2026-68155