Vulnerability · Published Oct 30, 2025 · Assigned by Linux

CVE-2025-40099cifs: parse_dfs_referrals: prevent oob on malformed input

Critical 9.4

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 35% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.4Critical
Exploit odds (30 days)0.4%top 64.9% 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: parse_dfs_referrals: prevent oob on malformed input Malicious SMB server can send invalid reply to FSCTL_DFS_GET_REFERRALS - reply smaller than sizeof(struct get_dfs_referral_rsp) - reply with number of referrals smaller than NumberOfReferrals in the header Processing of such replies will cause oob. Return -EINVAL error on such replies to prevent oob-s.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.158-1DEBIAN-CVE-2025-40099
Debian:13linux6.12.57-1DEBIAN-CVE-2025-40099
Debian:14linux6.17.6-1DEBIAN-CVE-2025-40099
Ubuntu:22.04:LTSlinuxno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux6.8.0-106.106UBUNTU-CVE-2025-40099
Ubuntu:25.10linux6.17.0-14.14UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-awsno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-aws6.8.0-1050.53UBUNTU-CVE-2025-40099
Ubuntu:25.10linux-aws6.17.0-1007.7UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-aws-6.176.17.0-1007.7~24.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1050.53~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azureno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure6.8.0-1051.57UBUNTU-CVE-2025-40099
Ubuntu:25.10linux-azure6.17.0-1008.8UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1051.57~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure-fde6.8.0-1058.65UBUNTU-CVE-2025-40099
Ubuntu:25.10linux-azure-fdeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-azure-fde-6.86.8.0-1058.65~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-gcp6.8.0-1052.55UBUNTU-CVE-2025-40099
Ubuntu:25.10linux-gcp6.17.0-1007.7UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-gcp-6.176.17.0-1008.8~24.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1052.55~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-gke6.8.0-1048.53UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1035.38UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-hwe-6.86.8.0-106.106~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-ibm6.8.0-1049.49UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1049.49~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-intel-iotgno fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-kvmno fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-106.106.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-106.106.1~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1049.52UBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-nvidia-6.176.17.0-1008.8UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1049.52~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1049.52.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1020.20UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-nvidia-tegra-igxno fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oem-6.176.17.0-1011.11UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oracle6.8.0-1047.48UBUNTU-CVE-2025-40099
Ubuntu:25.10linux-oracle6.17.0-1007.7UBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-oracle-6.176.17.0-1007.7~24.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1047.48~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-raspino fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-raspi6.8.0-1050.54UBUNTU-CVE-2025-40099
Ubuntu:25.10linux-raspi6.17.0-1008.8UBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2025-40099
Ubuntu:25.10linux-realtime6.17.0-1006.7UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2025-40099
Ubuntu:25.10linux-riscv6.17.0-14.14.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-riscv-6.86.8.0-106.106~22.04.1UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2025-40099
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1028.29UBUNTU-CVE-2025-40099
Ubuntu:22.04:LTSlinux-xilinx-zynqmpno fix listedUBUNTU-CVE-2025-40099

Affected products (as reported)

VendorProductVersions
Linux Linux 4ecce920e13ace16a5ba45efe8909946c28fb2ad – before cfacc7441f760e4a73cc71b6ff1635261d5346574ecce920e13ace16a5ba45efe8909946c28fb2ad – before 15c73964da9df994302f579ed14ee5fdbce7a3324ecce920e13ace16a5ba45efe8909946c28fb2ad – before 8bc4a8d39bac23d8b044fd3e2dbfd965f1d9b0584ecce920e13ace16a5ba45efe8909946c28fb2ad – before bb0f2e66e1ac043a5b238f5bcab4f26f3c3170394ecce920e13ace16a5ba45efe8909946c28fb2ad – before 6447b0e355562a1ff748c4a2ffb89aae7e84d2c9
Linux Linux 4.11

References