SB20261022148 - Use-after-free in Linux kernel stmicro stmmac driver

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-98571)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause memory corruption that may result in a denial of service.

The vulnerability exists due to use-after-free in the Linux kernel stmmac receive path when napi_build_skb() fails during packet reception. The recycled page remains referenced by buf->page, causing stmmac_rx_refill() to skip replacement allocation and program the already-recycled page into an RX descriptor. A local user can exploit this stale page reference to potentially corrupt kernel memory and cause a denial of service.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0a7822e34a0bfde31b194ac3da3253e5032b44cc
• https://git.kernel.org/stable/c/298673397ea3f6f5811b84f0d9f71eac71dda2e3
• https://git.kernel.org/stable/c/501baaeca7d128fa0a2f6953cf5873c5b0d7cf89