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.
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
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.170-1 | DEBIAN-CVE-2026-43458 |
| Debian:13 | linux | 6.12.85-1 | DEBIAN-CVE-2026-43458 |
| Debian:14 | linux | 6.19.10-1 | DEBIAN-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux | 5.15.0-186.196 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux | 6.8.0-136.136 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1112.119 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1061.64 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-aws | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | 6.8.0-1061.64~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1117.126 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1063.71 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-azure | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | 6.8.0-1063.71~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1117.126 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-fde | 6.8.0-1062.69 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | 6.8.0-1062.69~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1112.122 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1064.72 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-gcp | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | 6.8.0-1064.72~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1108.114 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1059.67 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1095.103 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1046.50 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | 6.8.0-136.136~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1106.110 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1061.62 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | 6.8.0-1061.62~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1107.113 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1104.109 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-184.194 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-136.136.2 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | 6.8.0-136.136.2~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1107.108 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-nvidia | 6.8.0-1059.62 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | 6.8.0-1059.62~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | 6.8.0-1059.62.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1064.66 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1030.31 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1053.53 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1109.115 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1058.61 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-oracle | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | 6.8.0-1058.61~22.04.1 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-raspi | 5.15.0-1106.109 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-raspi | 6.8.0-1061.65 | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-raspi | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-realtime | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:25.10 | linux-riscv | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | 6.8.0-136.136~22.04.3 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-vmware | 6.8.0-1008.8 | UBUNTU-CVE-2026-43458 |
| Ubuntu:24.04:LTS | linux-xilinx | 6.8.0-1033.34 | UBUNTU-CVE-2026-43458 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1075.79 | UBUNTU-CVE-2026-43458 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| 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
- https://git.kernel.org/stable/c/23a3ac2e2262a291498567418227b99e1f3606b1
- https://git.kernel.org/stable/c/52135420e9f75853ea0c6cea7b736e3e98495f7d
- https://git.kernel.org/stable/c/ca2ceba983bb23ea0202c2882d963253416654a3
- https://git.kernel.org/stable/c/8460187b4852fd00bd1c76394358053f3fa4d089
- https://git.kernel.org/stable/c/27e43356d0defb9fc7fa25265219a3ffeb7b3e98
- https://git.kernel.org/stable/c/35b58d3bc716ebb9ebd10fe1cac8c1177242511c
- https://git.kernel.org/stable/c/97a0bb491cae39478c6225381f14e9ac67b7bba7
- https://git.kernel.org/stable/c/288598d80a068a0e9281de35bcb4ce495f189e2a