Vulnerability · Published Sep 25, 2026 · Assigned by Linux

CVE-2026-97568mptcp: syncookies: remember the request backup flag

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 12% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS )–Not rated
Exploit odds (30 days)0.2%top 87.9% 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: mptcp: syncookies: remember the request backup flag Instead of using an uninitialised bit when copying the info in subflow_ulp_clone(). To fix this, no need to extend the join_entry structure: backup is coming from struct mptcp_subflow_request_sock, only one bit. Do the same here by using one bit for both.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.190-1DEBIAN-CVE-2026-97568
Debian:13linux6.12.111-1DEBIAN-CVE-2026-97568
Debian:14linux7.2.7-1DEBIAN-CVE-2026-97568
Debian:12linux-6.126.12.111-1~deb12u1DEBIAN-CVE-2026-97568
Ubuntu:22.04:LTSlinux5.15.0-202.212UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinuxno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux7.0.0-42.42UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-aws5.15.0-1119.126UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-awsno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-aws7.0.0-1016.17UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-aws-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-aws-7.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure5.15.0-1125.134UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-azureno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-7.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-fde5.15.0-1124.133UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-azure-fdeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-fde-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-azure-fde-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-fde-7.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gcp5.15.0-1120.130UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gcpno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-gcp7.0.0-1016.18UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gcp-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gcp-7.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gke5.15.0-1115.121UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-gkeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-gkeop5.15.0-1102.110UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-gkeopno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-hwe-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-hwe-7.07.0.0-42.42~24.04.1UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-ibm5.15.0-1113.117UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-ibmno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-ibm7.0.0-1017.17UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-ibm-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-intel-iotg5.15.0-1114.120UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-kvm5.15.0-1111.116UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-lowlatency5.15.0-197.207UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-lowlatencyno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-nvidia5.15.0-1114.115UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-nvidiano fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-nvidia-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-nvidia-7.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-nvidia-bosno fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-nvidia-lowlatencyno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-nvidia-tegra5.15.0-1070.72UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-nvidia-tegrano fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-nvidia-tegra-igx5.15.0-1059.59UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-oem-7.07.0.0-1017.17UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oracle5.15.0-1116.122UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oracleno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-oracle7.0.0-1015.16UBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-oracle-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-oracle-7.0no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-raspino fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-97568
Ubuntu:26.04:LTSlinux-riscv7.0.0-42.42.1UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-riscv-6.8no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-riscv-7.07.0.0-42.42.1~24.04.1UBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-vmwareno fix listedUBUNTU-CVE-2026-97568
Ubuntu:24.04:LTSlinux-xilinxno fix listedUBUNTU-CVE-2026-97568
Ubuntu:22.04:LTSlinux-xilinx-zynqmpno fix listedUBUNTU-CVE-2026-97568

Affected products (as reported)

VendorProductVersions
Linux Linux 1008f2bcbc8e461c1df3aebba30ac4f616ebe570 – before c97fa2c7ada82d4cac1c6c00643238dc4c462f156f01f41b6a492ddf2da7609967cfaf57e7ca48a7 – before 1668b34452009d27be3262646de748a3e48ffd5109176f80995105c62939728fbad5c437d61e7ff4 – before b138e7dc719f0a3949de8bb6500b8cf1604eea068ed3e34c766e8264d5d2e0436f86c51604d6a8a7 – before 360d99258a6402cb8e49771460944f19f04d25b7efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 – before 61178d0b85b4b1b53e78b06e89d018d22d102f88efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 – before 00b2bd518911e0daab00f4749cce68c191ccebb4efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 – before 06d649f9cd03a9f8e768a658b20acf8d2c8022e0efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 – before b76c0e28b392620dfbaf92cdeedbf115820b44cb
Linux Linux 6.11

References