CVE-2026-43405 (GCVE-0-2026-43405)
Vulnerability from cvelistv5
Published
2026-05-08 14:21
Modified
2026-10-19 19:16
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: libceph: Use u32 for non-negative values in ceph_monmap_decode() This patch fixes unnecessary implicit conversions that change signedness of blob_len and num_mon in ceph_monmap_decode(). Currently blob_len and num_mon are (signed) int variables. They are used to hold values that are always non-negative and get assigned in ceph_decode_32_safe(), which is meant to assign u32 values. Both variables are subsequently used as unsigned values, and the value of num_mon is further assigned to monmap->num_mon, which is of type u32. Therefore, both variables should be of type u32. This is especially relevant for num_mon. If the value read from the incoming message is very large, it is interpreted as a negative value, and the check for num_mon > CEPH_MAX_MON does not catch it. This leads to the attempt to allocate a very large chunk of memory for monmap, which will most likely fail. In this case, an unnecessary attempt to allocate memory is performed, and -ENOMEM is returned instead of -EINVAL.
References
Impacted products
Vendor Product Version
Linux Linux Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
Version: a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c
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}


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