Vulnerability · Published Oct 23, 2026 · Assigned by Linux
CVE-2026-98900xen/gntalloc: validate grant count before allocation
Unrated
In plain English
A 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 0.2% (higher than 8% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
In the Linux kernel, the following vulnerability has been resolved: xen/gntalloc: validate grant count before allocation gntalloc_ioctl_alloc() allocates the grant-id array before checking whether the requested count fits within the global grant limit. Counts above that limit cannot succeed, so reject them before the user-controlled allocation reaches kcalloc(). Use a subtraction-based check while holding gref_mutex so adding the requested count cannot wrap. Also cast the count before advancing the per-file index so the page-size multiplication is performed in 64-bit arithmetic.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.190-1 | DEBIAN-CVE-2026-98900 |
| Debian:13 | linux | 6.12.111-1 | DEBIAN-CVE-2026-98900 |
| Debian:14 | linux | 7.2.6-1 | DEBIAN-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux | 5.15.0-202.212 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux | 7.0.0-42.42 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1119.126 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-aws | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-aws | 7.0.0-1016.17 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-aws-7.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1125.134 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-azure | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-7.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1124.133 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-fde-7.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1120.130 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gcp | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-gcp | 7.0.0-1016.18 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gcp-7.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1115.121 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gke | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-gke | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1102.110 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-gkeop | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-hwe-7.0 | 7.0.0-42.42~24.04.1 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1113.117 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-ibm | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-ibm | 7.0.0-1017.17 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1114.120 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1111.116 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-197.207 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-lowlatency | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1114.115 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-nvidia-7.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-nvidia-bos | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1070.72 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1059.59 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-oem-7.0 | 7.0.0-1017.17 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1116.122 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oracle | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-oracle | 7.0.0-1015.16 | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-oracle-7.0 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:26.04:LTS | linux-riscv | 7.0.0-42.42.1 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-riscv-7.0 | 7.0.0-42.42.1~24.04.1 | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-vmware | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:24.04:LTS | linux-xilinx | no fix listed | UBUNTU-CVE-2026-98900 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | no fix listed | UBUNTU-CVE-2026-98900 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | dd3140588d9551235ebc2a0dacdca098e7677573 – before e2806390aa1c4d5b3f7a68f10a56ae12c71c00d8dd3140588d9551235ebc2a0dacdca098e7677573 – before 71a0cf87e19fb35c4292ca88985e376e613c900add3140588d9551235ebc2a0dacdca098e7677573 – before 641de086a05f349de7fc548612432bc2fed721cadd3140588d9551235ebc2a0dacdca098e7677573 – before 720554c04acba80018ded069d3e0984bebaee891dd3140588d9551235ebc2a0dacdca098e7677573 – before 84d5727cef8eb9c8a28210ad248f1c70b223b065dd3140588d9551235ebc2a0dacdca098e7677573 – before 231542f4e43cf9837cb520664545e85fbe666b7bdd3140588d9551235ebc2a0dacdca098e7677573 – before 2299822f3f466b5dcad2377bf63986199f881a6b |
| Linux | Linux | 2.6.39 |
References
- https://git.kernel.org/stable/c/e2806390aa1c4d5b3f7a68f10a56ae12c71c00d8
- https://git.kernel.org/stable/c/71a0cf87e19fb35c4292ca88985e376e613c900a
- https://git.kernel.org/stable/c/641de086a05f349de7fc548612432bc2fed721ca
- https://git.kernel.org/stable/c/720554c04acba80018ded069d3e0984bebaee891
- https://git.kernel.org/stable/c/84d5727cef8eb9c8a28210ad248f1c70b223b065
- https://git.kernel.org/stable/c/231542f4e43cf9837cb520664545e85fbe666b7b
- https://git.kernel.org/stable/c/2299822f3f466b5dcad2377bf63986199f881a6b