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Vulnerability · Published Sep 24, 2026 · Assigned by Linux

CVE-2026-93798btrfs: fix reloc root cleanup in merge_reloc_roots()

High 7.8

In plain English

A high-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 0.1% (higher than 3% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.1%top 97.4% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix reloc root cleanup in merge_reloc_roots() If the root we got has zero root refs in its root item, we are resetting the root's ->reloc_root without using barriers like we do everywhere else. Sashiko complained about this while reviewing another patch, and it's correct (see the Link tag below). Also, we should not clear BTRFS_ROOT_DEAD_RELOC_TREE from the root unless the root points to the reloc root we have. Fix this by using clear_reloc_root(), which issues the memory barrier after setting the root's ->reloc_root to NULL and before clearing the bit BTRFS_ROOT_DEAD_RELOC_TREE from the root.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.190-1DEBIAN-CVE-2026-93798
Debian:13linux6.12.111-1DEBIAN-CVE-2026-93798
Debian:14linux7.2.6-1DEBIAN-CVE-2026-93798
Debian:12linux-6.126.12.111-1~deb12u1DEBIAN-CVE-2026-93798
Ubuntu:22.04:LTSlinux5.15.0-202.212UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinuxno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux7.0.0-42.42UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-aws5.15.0-1119.126UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-aws7.0.0-1016.17UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-aws-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-aws-7.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure5.15.0-1125.134UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-7.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-fde5.15.0-1124.133UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-fde-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-azure-fde-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-fde-7.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gcp5.15.0-1120.130UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-gcp7.0.0-1016.18UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gcp-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gcp-7.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gke5.15.0-1115.121UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-gkeop5.15.0-1102.110UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-hwe-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-hwe-7.07.0.0-42.42~24.04.1UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-ibm5.15.0-1113.117UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-ibm7.0.0-1017.17UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-ibm-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-intel-iotg5.15.0-1114.120UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-kvm5.15.0-1111.116UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-lowlatency5.15.0-197.207UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-nvidia5.15.0-1114.115UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-nvidia-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-nvidia-7.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-nvidia-bosno fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-nvidia-lowlatencyno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-nvidia-tegra5.15.0-1070.72UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-nvidia-tegra-igx5.15.0-1059.59UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-oem-7.07.0.0-1017.17UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oracle5.15.0-1116.122UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-oracle7.0.0-1015.16UBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-oracle-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-oracle-7.0no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-93798
Ubuntu:26.04:LTSlinux-riscv7.0.0-42.42.1UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-riscv-6.8no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-riscv-7.07.0.0-42.42.1~24.04.1UBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-vmwareno fix listedUBUNTU-CVE-2026-93798
Ubuntu:24.04:LTSlinux-xilinxno fix listedUBUNTU-CVE-2026-93798
Ubuntu:22.04:LTSlinux-xilinx-zynqmpno fix listedUBUNTU-CVE-2026-93798

Affected products (as reported)

VendorProductVersions
Linux Linux 1dae7e0e58b484eaa43d530f211098fdeeb0f404 – before 29531470b1bf1e8bd2df4941fe913106edbca6151dae7e0e58b484eaa43d530f211098fdeeb0f404 – before 415f8665a969d3c906e4fd7c90fcbb4b357886f61dae7e0e58b484eaa43d530f211098fdeeb0f404 – before ee695a968aa73b1e67ccbf2133dc0e54381d32b21dae7e0e58b484eaa43d530f211098fdeeb0f404 – before 0bc25f0a2d1b3e0a691431c4d7aef36afcd527c51dae7e0e58b484eaa43d530f211098fdeeb0f404 – before ab48583aa9948205ff9a6470e23dbff74c565e241dae7e0e58b484eaa43d530f211098fdeeb0f404 – before 63d6b1f04cd91c825329712aa526215ffa5d11ca1dae7e0e58b484eaa43d530f211098fdeeb0f404 – before b78fe9563e2d5ae47805f1e5dc722c91fd30e1f8ee08663380ffd5a45a1c87580fbc305e8413c235
Linux Linux 5.8

References