Vulnerability · Published Jun 24, 2026 · Assigned by Linux
CVE-2026-52955libceph: Fix potential out-of-bounds access in crush_decode()
Critical 9.8
In plain English
A critical-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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().
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.176-1 | DEBIAN-CVE-2026-52955 |
| Debian:13 | linux | 6.12.94-1 | DEBIAN-CVE-2026-52955 |
| Debian:14 | linux | 7.0.10-1 | DEBIAN-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux | 5.15.0-186.196 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux | 6.8.0-136.136 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux | 7.0.0-28.28 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1112.119 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1061.64 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-aws | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-aws | 7.0.0-1009.9 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | 6.8.0-1061.64~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1117.126 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1063.71 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-azure | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-azure | 7.0.0-1010.10 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | 6.8.0-1063.71~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-7.0 | 7.0.0-1014.14~24.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1117.126 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-fde | 6.8.0-1062.69 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-azure-fde | 7.0.0-1009.9 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | 6.8.0-1062.69~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-fde-7.0 | 7.0.0-1013.13~24.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1112.122 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1064.72 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-gcp | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-gcp | 7.0.0-1008.8 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | 6.8.0-1064.72~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gcp-7.0 | 7.0.0-1011.11~24.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1108.114 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1059.67 | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-gke | 7.0.0-1003.4 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1095.103 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1046.50 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | 6.8.0-136.136~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-hwe-7.0 | 7.0.0-28.28~24.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1106.110 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1061.62 | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-ibm | 7.0.0-1010.10 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | 6.8.0-1061.62~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1107.113 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1104.109 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-184.194 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-136.136.2 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | 6.8.0-136.136.2~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1107.108 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-nvidia | 6.8.0-1059.62 | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-nvidia | 7.0.0-1016.16 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | 6.17.0-1032.32 | USN-8748-1 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | 6.17.0-1032.32 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | 6.8.0-1059.62~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-nvidia-7.0 | 7.0.0-1016.16~24.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-nvidia-bos | 7.0.0-2016.16 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | 6.8.0-1059.62.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1064.66 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1030.31 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1053.53 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | 6.17.0-1033.33 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | 6.17.0-1033.33 | USN-8911-1 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-oem-7.0 | 7.0.0-1009.9 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1109.115 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1058.61 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-oracle | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-oracle | 7.0.0-1008.8 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | 6.8.0-1058.61~22.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-oracle-7.0 | 7.0.0-1011.11~24.04.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-raspi | 5.15.0-1106.109 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-raspi | 6.8.0-1061.65 | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-raspi | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-raspi | 7.0.0-1015.15 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-realtime | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-realtime | 7.0.0-28.28.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:25.10 | linux-riscv | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:26.04:LTS | linux-riscv | 7.0.0-28.28.1 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | 6.8.0-136.136~22.04.3 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-riscv-7.0 | 7.0.0-28.28.1~24.04.3 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-vmware | 6.8.0-1008.8 | UBUNTU-CVE-2026-52955 |
| Ubuntu:24.04:LTS | linux-xilinx | 6.8.0-1033.34 | UBUNTU-CVE-2026-52955 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1075.79 | UBUNTU-CVE-2026-52955 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | f24e9980eb860d8600cbe5ef3d2fd9295320d229 – before 6e70ef53e818c53eab28d7b0026b7fd03dddaba5f24e9980eb860d8600cbe5ef3d2fd9295320d229 – before ebe76d58a48a48031b98543d86c4cd30a825b622f24e9980eb860d8600cbe5ef3d2fd9295320d229 – before 3f42508191e129ee6b5ea96578d5cab14f2a013af24e9980eb860d8600cbe5ef3d2fd9295320d229 – before ea0d42137f0c06da71e37ffc647aab4c5309599af24e9980eb860d8600cbe5ef3d2fd9295320d229 – before cceb10023e76bc89f3fe9238ebd0ccab0fc7c7c5f24e9980eb860d8600cbe5ef3d2fd9295320d229 – before 0f3604cbe4df14c5e58288ac9f57511e726a222df24e9980eb860d8600cbe5ef3d2fd9295320d229 – before fb176a99e4c1a5a8448a83d83d3606203ba81faaf24e9980eb860d8600cbe5ef3d2fd9295320d229 – before 4c79fc2d598694bda845b46229c9d48b65042970 |
| Linux | Linux | 2.6.34 |
Weakness: CWE-131 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://git.kernel.org/stable/c/6e70ef53e818c53eab28d7b0026b7fd03dddaba5
- https://git.kernel.org/stable/c/ebe76d58a48a48031b98543d86c4cd30a825b622
- https://git.kernel.org/stable/c/3f42508191e129ee6b5ea96578d5cab14f2a013a
- https://git.kernel.org/stable/c/ea0d42137f0c06da71e37ffc647aab4c5309599a
- https://git.kernel.org/stable/c/cceb10023e76bc89f3fe9238ebd0ccab0fc7c7c5
- https://git.kernel.org/stable/c/0f3604cbe4df14c5e58288ac9f57511e726a222d
- https://git.kernel.org/stable/c/fb176a99e4c1a5a8448a83d83d3606203ba81faa
- https://git.kernel.org/stable/c/4c79fc2d598694bda845b46229c9d48b65042970
- https://access.redhat.com/security/cve/CVE-2026-52955 vdb-entry, x_refsource_REDHAT
- RHBZ#2492328 issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52955.json x_sadp-csaf-vex