CVE-2026-80602

Not scored yetLast modified Oct 30, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

perf/x86/amd/lbr: Fix kernel address leakage

A user-only branch stack can contain branches that originate from the kernel. As a result, kernel addresses are exposed to user space even when PERF_SAMPLE_BRANCH_USER is requested. On AMD processors supporting X86_FEATURE_AMD_LBR_V2, perf can still report SYSRET/ERET entries for which the branch-from addresses are in the kernel.

E.g.

$ perf record -e cycles -o - -j any,save_type,u -- \ perf bench syscall basic --loop 1000 | \ perf script -i - -F brstack|tr ' ' '\n'| \ grep -E '0x[89a-f][0-9a-f]{15}'

... 0xffffffff81001268/0x717a90a38f1a/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a39157/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a2c628/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a41b60/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a260db/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a90a260db/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a8bef1c30/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH 0xffffffff81001268/0x717a8e4d3c90/M/-/-/0/ERET/NON_SPEC_CORRECT_PATH ...

The reason is that the hardware filter only considers the privilege level applicable to the branch target. Extend software filtering to also validate the branch-from addresses against br_sel, so that any branch record whose branch-from address is in the kernel is dropped when PERF_SAMPLE_BRANCH_USER is requested.

Metrics

No CVSS score has been published yet.

Affected software

Source: the vendor's advisory (CNA). NVD analysis pending.

VendorProductVersions
LinuxLinux>= f4f925dae7419fc7a10af539c073871927ce3a24, < 5adfec05e804ce4bd3368b75df5e5b7b40ee960b; >= f4f925dae7419fc7a10af539c073871927ce3a24, < 5be478c1e08981ca91b34de310d7e2638171d9d8; >= f4f925dae7419fc7a10af539c073871927ce3a24, < 208ecca408b1707ad86ea247d3d3e09d3606fc13; >= f4f925dae7419fc7a10af539c073871927ce3a24, < 5ab0eba9c8819506bcb72348fd701f8a9006f95e; >= f4f925dae7419fc7a10af539c073871927ce3a24, < fb3b76b5ad2ebad63dd76f8b65b624eaf638b73f; >= f4f925dae7419fc7a10af539c073871927ce3a24, < 2a892294b83f541115c94b0bb637f39bef187657
LinuxLinux6.1

References

Timeline

Published
Aug 28, 2026
Last modified
Oct 30, 2026
NVD status
Received

Related CVEs from 2026

CVE-2026-806039.1In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_irc: fix parse_dcc() off-by-one OOB read parseCVE-2026-806048.8In the Linux kernel, the following vulnerability has been resolved: HID: core: Fix OOB read in hid_get_report for numbered reports When a CVE-2026-80605In the Linux kernel, the following vulnerability has been resolved: HID: picolcd: prevent NULL pointer dereference in picolcd_send_and_waitCVE-2026-806067.8In the Linux kernel, the following vulnerability has been resolved: drm/xe/userptr: Hold notifier_lock for write on inject test path When CVE-2026-80607In the Linux kernel, the following vulnerability has been resolved: tracing/probes: Remove WARN_ON_ONCE from parse_btf_arg Sashiko found tCVE-2026-806088.8In the Linux kernel, the following vulnerability has been resolved: accel/amdxdna: Fix iommu domain lifetime race during device removal WhCVE-2026-806099.8In the Linux kernel, the following vulnerability has been resolved: qede: fix out-of-bounds check for cqe->len_list[] Move index check befCVE-2026-80610In the Linux kernel, the following vulnerability has been resolved: net: enetc: fix potential divide-by-zero when num_vsi is zero For i.MXCVE-2026-80611In the Linux kernel, the following vulnerability has been resolved: ACPI: processor_idle: Mark LPI enter functions as __cpuidle When functCVE-2026-806129.8In the Linux kernel, the following vulnerability has been resolved: net: lwtunnel: Drop skb metadata before LWT encapsulation skb metadataCVE-2026-806137.8In the Linux kernel, the following vulnerability has been resolved: veth: fix NAPI leak in XDP enable error path During XDP enablement in CVE-2026-806147.5In the Linux kernel, the following vulnerability has been resolved: net: emac: Fix NULL pointer dereference in emac_probe Move devm_reques
CVE-2026-80602: Unscored | Vulnix