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[ CVE-2026-98039 · Published 25 Sep 2026 ]

Vulnerability in Linux

Not scored yet EPSS <1%3 agency advisoriesNo fix listed yet

[ Description ]Official description

In the Linux kernel, the following vulnerability has been resolved: bpf: Require MEM_PERCPU for percpu kptr stores map_kptr_match_type() treats perm_flags as the set of register type flags that a kptr field permits. Adding MEM_PERCPU to that set for BPF_KPTR_PERCPU does not require the source register to carry it, however. The subset test consequently accepts both a plain bpf_obj_new() allocation and a referenced kernel pointer into a __percpu_kptr map field. Loads from the field are always marked MEM_PERCPU. Consumers then treat the stored value as the cookie returned by bpf_percpu_obj_new(): per-CPU pointer helpers relocate it, and map teardown selects the per-CPU free path. A plain allocation can therefore provide an arbitrary kernel read/write, while a kernel pointer can be relocated into an invalid address or sent through a missing destructor. Require the source MEM_PERCPU flag to match the destination field kind. This preserves valid bpf_percpu_obj_new() stores and rejects both the program-BTF and kernel-BTF variants.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

  • CERT-FRCERTFR-2026-AVI-1289

    Multiple vulnerabilities in the Debian LTS Linux kernel Translated from French

    Multiple vulnerabilities have been discovered in the Debian LTS Linux kernel. Some of them allow an attacker to cause privilege escalation, a breach of data confidentiality and denial of service.

    CVE-2025-38237CVE-2025-39833CVE-2025-39925+1311 more CVEs
  • CERT-FRCERTFR-2026-AVI-1253

    Multiple vulnerabilities in the Debian Linux kernel Translated from French

    Multiple vulnerabilities have been discovered in the Debian Linux kernel. Some of them allow an attacker to cause privilege escalation, a breach of data confidentiality and denial of service.

    CVE-2025-38237CVE-2025-39833CVE-2025-39925+1310 more CVEs
  • BSI CERT-BundWID-SEC-2026-3579

    Linux Kernel: Multiple vulnerabilities Translated from German

    CVE-2026-97615CVE-2026-97978CVE-2026-98127+590 more CVEs

[ References ]References