CVE Catalog

CVE-2026-52957

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.53%

41th percentile - higher than 41% of all known CVEs

Summary

In the Linux kernel's libceph library, a null pointer dereference vulnerability was found during decoding of choose_args in the CRUSH map. The issue occurs when a received message contains a bucket_index pointing to a non-existent (NULL) bucket, potentially causing a system crash.

Risk Assessment

An attacker can send a crafted CEPH_MSG_OSD_MAP message causing a null pointer dereference in the kernel, leading to a system panic and potential denial of service.

Recommendation

Immediately update the Linux kernel to a version containing the fix (commit 5a8e7f3b2c1d), which adds a NULL check before accessing the bucket.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential null-ptr-deref in decode_choose_args() A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself contains a CRUSH map. When decoding this CRUSH map in crush_decode(), an array of max_buckets CRUSH buckets is decoded, where some indices may not refer to actual buckets and are therefore set to NULL. The received CRUSH map may optionally contain choose_args that get decoded in decode_choose_args(). When decoding a crush_choose_arg_map, a series of choose_args for different buckets is decoded, with the bucket_index being read from the incoming message. It is only checked that the bucket index does not exceed max_buckets, but not that it doesn't point to an index with a NULL bucket. If a (potentially corrupted) message contains a crush_choose_arg_map including such a bucket_index, a null pointer dereference may occur in the subsequent processing when attempting to access the bucket with the given index. This patch fixes the issue by extending the affected check. Now, it is only attempted to access the bucket if it is not NULL.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS