CVE-2026-89731: Linux

High severity, CVSS 7.1. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: cxl/ras: Fix cxl_rch_get_aer_info() out-of-bounds AER register read cxl_rch_get_aer_info() copies the RCH Downstream Port AER capability from the RCRB MMIO block using a readl() loop bounded by sizeof(struct aer_capability_regs). This struct is a software layout and its embedded struct pcie_tlp_log is larger than the on-wire AER capability. As a result the loop reads past the mapped AER register block. The over-read also populates the software-only tail fields including header_log.header_len. An out-of-range header_len passed to pcie_print_tlp_log() can then loop past the header log buffer and cause a second out-of-bounds read. The read was correct when introduced, but struct pcie_tlp_log has since grown (Header Log and TLP Prefix Log sizes, header_len and flit fields), so sizeof(struct aer_capability_regs) no longer matches the physical AER capability. Bound the read to the physical AER registers, header through the 16 byte Header Log. Zero the destination first so the software-only fields are deterministic.

Affected products

• Linux Linux: from 6.7, before 6.12.111 (fixed in 6.12.111); from 6.13, before 6.18.51 (fixed in 6.18.51); from 6.19, before 7.2.4 (fixed in 7.2.4)

Published 2026-09-11. Last modified 2026-09-21.