Junglewise Threat Intelligence

CVE-2026-43203: Linux Kernel use-after-free in fore200e ATM driver during device removal

CVE-2026-43203 · Severity: high · CVSS 7.5 · Published 2026-05-06

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability exists in the Linux kernel's FORE200E ATM network adapter driver. When the network hardware is removed or detached from the system, a race condition can occur where the system attempts to access memory that has already been freed. This can lead to system instability, crashes, or potential unauthorized code execution.

Technical details

A use-after-free (UAF) vulnerability exists in the drivers/atm/fore200e.c component of the Linux kernel. The issue stems from a race condition during device detachment (fore200e_pca_remove_one) where the fore200e structure is deallocated while tx_tasklet or rx_tasklet may still be scheduled or running. An attacker could potentially exploit this race condition to trigger a UAF when fore200e_tx_tasklet() or fore200e_rx_tasklet() accesses the freed memory. The fix involves implementing tasklet_kill() within the fore200e_shutdown() sequence to ensure all pending tasklets are synchronized and terminated before the memory is released. This bug was identified via static analysis and affects systems using PCA-200E or SBA-200E adapters.

Affected products

  • Linux Linux Kernel versions from 2.6.12.1 up to 5.10.252; 5.11 up to 5.15.202; 5.16 up to 6.1.165; 6.2 up to 6.6.128; 6.7 up to 6.12.75; 6.13 up to 6.18.16; 6.19 up to 6.19.6

Timeline

  • 2026-02-10: patched: Initial patch authored by Duoming Zhou
  • 2026-05-06: disclosed: CVE published

References

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