Description
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.
References8
- git.kernel.org/stable/c/05f90284223381005d6bcddab3fda4a97f9c3401
- git.kernel.org/stable/c/146461f09565afe3665e65b0423d3d6b0fe806c5
- git.kernel.org/stable/c/3b2f1937f5fce8b7dd5432e7693e3cc8b5eece56
- git.kernel.org/stable/c/70998f91030ee083ecb336a1dff0701c20a38081
- git.kernel.org/stable/c/80fc40e11cda1b5d990a3f69c6efa344fb5cd987
- git.kernel.org/stable/c/826cd1de5802fd392922785f9b64d76e65d2a100
- git.kernel.org/stable/c/952ca5dc99913d169263f59fd689f586729a13c1
- git.kernel.org/stable/c/b8a9fb6bf806f9c4891e71ae1beab0c07c23a877
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 54 · as of 12 November 2026
- CWE
- CWE-20
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