CVE-2026-52955 (GCVE-0-2026-52955)
Vulnerability from cvelistv5
Published
2026-06-24 16:28
Modified
2026-08-05 12:32
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in crush_decode() A message of type CEPH_MSG_OSD_MAP containing a crush map with at least one bucket has two fields holding the bucket algorithm. If the values in these two fields differ, an out-of-bounds access can occur. This is the case because the first algorithm field (alg) is used to allocate the correct amount of memory for a bucket of this type, while the second algorithm field inside the bucket (b->alg) is used in the subsequent processing. This patch fixes the issue by adding a check that compares alg and b->alg and aborts the processing in case they differ. Furthermore, b->alg is set to 0 in this case, because the destruction of the crush map also uses this field to determine the bucket type, which can again result in an out-of-bounds access when trying to free the memory pointed to by the fields of the bucket. To correctly free the memory allocated for the bucket in such a case, the corresponding call to kfree is moved from the algorithm-specific crush_destroy_bucket functions to the generic crush_destroy_bucket().
References
Impacted products
Vendor Product Version
Linux Linux Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
Version: f24e9980eb860d8600cbe5ef3d2fd9295320d229
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}


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