Log in Start free

Vulnerability · Published Sep 11, 2026 · Assigned by Linux

CVE-2026-89640cifs: fix loff_t underflow in cifs_remap_file_range() when len == 0

High 7.1

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 2% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.1High
Exploit odds (30 days)0.1%top 97.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

In the Linux kernel, the following vulnerability has been resolved: cifs: fix loff_t underflow in cifs_remap_file_range() when len == 0 With len == 0 (clone to EOF), the effective length is computed as: len = src_inode->i_size - off; If off > i_size, this is a negative loff_t, corrupting the ByteCount in the FSCTL_DUPLICATE_EXTENTS_TO_FILE request and inverting the range in filemap_write_and_wait_range(). The existing off >= i_size check fires only after the ioctl has already been sent. Snapshot i_size_read() once for both the bounds check and the length calculation, eliminating the TOCTOU and 32-bit torn-read risk. Reject off > src_size with -EINVAL. Treat off == src_size as a no-op, consistent with __generic_remap_file_range_prep().

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.190-1DEBIAN-CVE-2026-89640
Debian:13linux6.12.111-1DEBIAN-CVE-2026-89640
Debian:14linux7.2.6-1DEBIAN-CVE-2026-89640
Debian:12linux-6.126.12.111-1~deb12u1DEBIAN-CVE-2026-89640
Ubuntu:22.04:LTSlinuxno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinuxno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux7.0.0-42.42UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-aws7.0.0-1016.17UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-aws-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-aws-7.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-7.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-fde-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-azure-fde-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-fde-7.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-gcp7.0.0-1016.18UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gcp-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gcp-7.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-hwe-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-hwe-7.07.0.0-42.42~24.04.1UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-ibm7.0.0-1017.17UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-ibm-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-intel-iotgno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-kvmno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-nvidia-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-nvidia-7.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-nvidia-bosno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-nvidia-lowlatencyno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1038.42UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-nvidia-tegra-igxno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-oem-7.07.0.0-1017.17UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-oracle7.0.0-1015.16UBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-oracle-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-oracle-7.0no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-89640
Ubuntu:26.04:LTSlinux-riscv7.0.0-42.42.1UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-riscv-6.8no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-riscv-7.07.0.0-42.42.1~24.04.1UBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-vmwareno fix listedUBUNTU-CVE-2026-89640
Ubuntu:24.04:LTSlinux-xilinxno fix listedUBUNTU-CVE-2026-89640
Ubuntu:22.04:LTSlinux-xilinx-zynqmpno fix listedUBUNTU-CVE-2026-89640

Affected products (as reported)

VendorProductVersions
Linux Linux 04b38d601239b4d9be641b412cf4b7456a041c67 – before 2c6eede83b3de1268db92c7e49741761c954aa2604b38d601239b4d9be641b412cf4b7456a041c67 – before ce813e5eebf46851e872ce59bdc34dc5dd4e29a404b38d601239b4d9be641b412cf4b7456a041c67 – before f3d1ae1e6bc4a9f559185b6e7bd2b6375ec2fdd404b38d601239b4d9be641b412cf4b7456a041c67 – before 7f62817fe049b0f3652518c1ba72631ec1e0a32204b38d601239b4d9be641b412cf4b7456a041c67 – before b098f5e5858797827666e6cd73033f52fc39b5f604b38d601239b4d9be641b412cf4b7456a041c67 – before c2a0dcb5a7a1516aa6eb6d5cedca6a8e7652702804b38d601239b4d9be641b412cf4b7456a041c67 – before b057ca17b656345d04669cb87f2aff9b31d873db04b38d601239b4d9be641b412cf4b7456a041c67 – before 6c322f5cf7476ded7a9a20f7be72462065a03c68
Linux Linux 4.5

References