Vulnerability · Published May 8, 2026 · Assigned by Linux

CVE-2026-43458serial: caif: hold tty->link reference in ldisc_open and ser_release

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

Severity (CVSS NVD)7.8High
Exploit odds (30 days)0.1%top 98.3% 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: serial: caif: hold tty->link reference in ldisc_open and ser_release A reproducer triggers a KASAN slab-use-after-free in pty_write_room() when caif_serial's TX path calls tty_write_room(). The faulting access is on tty->link->port. Hold an extra kref on tty->link for the lifetime of the caif_serial line discipline: get it in ldisc_open() and drop it in ser_release(), and also drop it on the ldisc_open() error path. With this change applied, the reproducer no longer triggers the UAF in my testing.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12linux6.1.170-1DEBIAN-CVE-2026-43458
Debian:13linux6.12.85-1DEBIAN-CVE-2026-43458
Debian:14linux6.19.10-1DEBIAN-CVE-2026-43458
Ubuntu:22.04:LTSlinux5.15.0-186.196UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux6.8.0-136.136UBUNTU-CVE-2026-43458
Ubuntu:25.10linuxno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-allwinner-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-aws5.15.0-1112.119UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-aws6.8.0-1061.64UBUNTU-CVE-2026-43458
Ubuntu:25.10linux-awsno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-aws-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-aws-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-aws-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-aws-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-aws-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-aws-6.86.8.0-1061.64~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure5.15.0-1117.126UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure6.8.0-1063.71UBUNTU-CVE-2026-43458
Ubuntu:25.10linux-azureno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-6.11no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-6.86.8.0-1063.71~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-fde5.15.0-1117.126UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-fde6.8.0-1062.69UBUNTU-CVE-2026-43458
Ubuntu:25.10linux-azure-fdeno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-fde-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-fde-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-fde-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-azure-fde-6.86.8.0-1062.69~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-nvidiano fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-azure-nvidia-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gcp5.15.0-1112.122UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-gcp6.8.0-1064.72UBUNTU-CVE-2026-43458
Ubuntu:25.10linux-gcpno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gcp-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-gcp-6.11no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-gcp-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-gcp-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gcp-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gcp-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gcp-6.86.8.0-1064.72~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gke5.15.0-1108.114UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-gke6.8.0-1059.67UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-gkeop5.15.0-1095.103UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-gkeop6.8.0-1046.50UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-hwe-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-hwe-6.11no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-hwe-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-hwe-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-hwe-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-hwe-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-hwe-6.86.8.0-136.136~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-ibm5.15.0-1106.110UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-ibm6.8.0-1061.62UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-ibm-6.86.8.0-1061.62~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-intel-iot-realtimeno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-intel-iotg5.15.0-1107.113UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-kvm5.15.0-1104.109UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-lowlatency5.15.0-184.194UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-lowlatency6.8.0-136.136.2UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-lowlatency-hwe-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-lowlatency-hwe-6.11no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-lowlatency-hwe-6.86.8.0-136.136.2~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-nvidia5.15.0-1107.108UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-nvidia6.8.0-1059.62UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-nvidia-6.11no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-nvidia-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-nvidia-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-nvidia-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-nvidia-6.86.8.0-1059.62~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-nvidia-lowlatency6.8.0-1059.62.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-nvidia-tegra5.15.0-1064.66UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-nvidia-tegra6.8.0-1030.31UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-nvidia-tegra-igx5.15.0-1053.53UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oem-5.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oem-6.0no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oem-6.1no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oem-6.11no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oem-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oem-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oem-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oem-6.8no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oracle5.15.0-1109.115UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oracle6.8.0-1058.61UBUNTU-CVE-2026-43458
Ubuntu:25.10linux-oracleno fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oracle-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-oracle-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oracle-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-oracle-6.86.8.0-1058.61~22.04.1UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-raspi5.15.0-1106.109UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-raspi6.8.0-1061.65UBUNTU-CVE-2026-43458
Ubuntu:25.10linux-raspino fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-raspi-realtimeno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-realtimeno fix listedUBUNTU-CVE-2026-43458
Ubuntu:25.10linux-realtimeno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-riscvno fix listedUBUNTU-CVE-2026-43458
Ubuntu:25.10linux-riscvno fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-riscv-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-riscv-6.14no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-riscv-6.17no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-riscv-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-riscv-6.86.8.0-136.136~22.04.3UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-starfive-5.19no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-starfive-6.2no fix listedUBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-starfive-6.5no fix listedUBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-vmware6.8.0-1008.8UBUNTU-CVE-2026-43458
Ubuntu:24.04:LTSlinux-xilinx6.8.0-1033.34UBUNTU-CVE-2026-43458
Ubuntu:22.04:LTSlinux-xilinx-zynqmp5.15.0-1075.79UBUNTU-CVE-2026-43458

Affected products (as reported)

VendorProductVersions
Linux Linux e31d5a05948e4478ba8396063d1e1f39880928e2 – before 23a3ac2e2262a291498567418227b99e1f3606b1e31d5a05948e4478ba8396063d1e1f39880928e2 – before 52135420e9f75853ea0c6cea7b736e3e98495f7de31d5a05948e4478ba8396063d1e1f39880928e2 – before ca2ceba983bb23ea0202c2882d963253416654a3e31d5a05948e4478ba8396063d1e1f39880928e2 – before 8460187b4852fd00bd1c76394358053f3fa4d089e31d5a05948e4478ba8396063d1e1f39880928e2 – before 27e43356d0defb9fc7fa25265219a3ffeb7b3e98e31d5a05948e4478ba8396063d1e1f39880928e2 – before 35b58d3bc716ebb9ebd10fe1cac8c1177242511ce31d5a05948e4478ba8396063d1e1f39880928e2 – before 97a0bb491cae39478c6225381f14e9ac67b7bba7e31d5a05948e4478ba8396063d1e1f39880928e2 – before 288598d80a068a0e9281de35bcb4ce495f189e2a
Linux Linux 2.6.35

References