Answer in brief
CVE-2026-43405 records a High severity (CVSS 7.5) vulnerability in libceph: Use u32 for non-negative values in ceph_monmap_decode(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <ee5588e2bc41acb73f6676c0520420c107cd0140 || >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <86f7060cd638d6eb042e8ed780fb83a59ca0dcb3 || >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <5f2806684b05bd24d05c091083b8e2517ba8ffac || >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <b268984ae88cb0dcd7a8e8263962c748448e26e8 || >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <ba0a4df8c563536857dcbf7b4dbd0f2a15f57ace || >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <08bc6173fd611ad5a40f472bf5f15b92aea0fe40 || >=a5cbd5fc22d5043a8a76e15d75d031fe24d1f69c <770444611f047dbfd4517ec0bc1b179d40c2f346 | ee5588e2bc41acb73f6676c0520420c107cd0140, 86f7060cd638d6eb042e8ed780fb83a59ca0dcb3, 5f2806684b05bd24d05c091083b8e2517ba8ffac, b268984ae88cb0dcd7a8e8263962c748448e26e8, ba0a4df8c563536857dcbf7b4dbd0f2a15f57ace, 08bc6173fd611ad5a40f472bf5f15b92aea0fe40, 770444611f047dbfd4517ec0bc1b179d40c2f346 |
| Linux/Linuxgeneric | 5.11 | Not reported |
Published upstream
May 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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.
Quoted source text, attributed separately from HOL analysis.