CVE-2026-68154
In the Linux kernel, the following vulnerability has been resolved:
libceph: reject zero bucket types in crush_decode
CRUSH bucket type 0 is reserved for devices. The mapper relies on
that invariant and uses type 0 to identify leaf devices.
If crush_decode() accepts a bucket with type 0, a malformed CRUSH map
can make the mapper treat a negative bucket ID as a device and pass it
to is_out(), which then indexes the OSD weight array with a negative
value.
Reject zero bucket types while decoding the CRUSH map so the invalid
state never reaches the mapper.
CSIRTS triage
- What
- libceph crush_decode() function fails to reject invalid zero bucket types in cluster maps.
- Who is affected
- Ceph storage systems and clients processing untrusted cluster maps.
- Urgency
- Medium severity (CVSS 5.5); rejection of zero bucket types prevents potential memory issues.
- Action
- Update to a patched Linux kernel version addressing CVE-2026-68154.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch CVE-2026-68154
Get an email if CVE-2026-68154 is added to CISA KEV, gains public exploit code, or a new advisory cites it — max one per day, one-click unsubscribe.
Exploitation outlook
- Low exploitation risk0.70% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 50% of all EPSS-scored CVEs.
Advisory coverage (2)
- mediumCVE-2026-68154: libceph: reject zero bucket types in crush_decodemsrc · 2026-08-11
- criticalCVE-2026-68154: In the Linux kernel, the following vulnerability has been resolved: libceph: reject zero bucke…nvd · 2026-08-10
External references
Embed the live status
— this badge updates automatically when the KEV or exploit status changes. How to embed it →
[](https://www.csirts.com/cve/CVE-2026-68154)