0.0
NA
CVE-2026-89731
cxl/ras: Fix cxl_rch_get_aer_info() out-of-bounds AER register read
Description

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.

INFO

Published Date :

Sept. 11, 2026, 8:20 p.m.

Last Modified :

Sept. 11, 2026, 8:20 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-89731 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Fix an out-of-bounds read in the kernel's AER register handling.
  • Update the Linux kernel to a patched version.
  • Bound register reads to physical AER registers.
  • Zero the destination buffer before copying.
  • Ensure struct sizes match physical capabilities.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-89731.

URL Resource
https://git.kernel.org/stable/c/29458e62d0829cbc99435f3e44fd560f9bbf1da7
https://git.kernel.org/stable/c/8bd3523df1319edc61cd391e695c84a4618516df
https://git.kernel.org/stable/c/8e3d9dbb25d3ddbe72b4542ec4f7c4e622fe0ced
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-89731 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-89731 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-89731 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-89731 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Sep. 11, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89731.json">CVE-2026-89731</a>
    Added Reference https://git.kernel.org/stable/c/29458e62d0829cbc99435f3e44fd560f9bbf1da7
    Added Reference https://git.kernel.org/stable/c/8bd3523df1319edc61cd391e695c84a4618516df
    Added Reference https://git.kernel.org/stable/c/8e3d9dbb25d3ddbe72b4542ec4f7c4e622fe0ced
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.