CVE-2026-72325 — perf/x86/amd/core: Avoid enabling BRS from the SVM reload path
In the Linux kernel, the following vulnerability has been resolved: perf/x86/amd/core: Avoid enabling BRS from the SVM reload path Branch Sampling (BRS) and Last Branch Record (LBR) are mutually exclusive hardware features, and users of both are tracked via cpuc->lbr_users. When SVM is toggled on a CPU, the host perf events are reprogrammed to update the HostOnly filter bit (set when virtualization is enabled, cleared when it is disabled). On PerfMonV2-capable processors, this reprogramming is performed by calling amd_pmu_enable_all() to rewrite the event selectors. However, amd_pmu_enable_all() also calls amd_brs_enable_all(), which enables BRS whenever cpuc->lbr_users > 0. Having active LBR events satisfies this gating on processors that have LBR but not BRS. The kernel then tries to set the BRS enable bit in DebugExtnCfg (MSR 0xc000010f). Since that bit is deprecated on such hardware, the write results in a #GP: Call Trace: <IRQ> amd_pmu_enable_all+0x1d/0x90 amd_pmu_disable_virt+0x62/0xb0 kvm_arch_disable_virtualization_cpu+0xa/0x40 [kvm] hardware_disable_nolock+0x1a/0x30 [kvm] __flush_smp_call_function_queue+0x9b/0x410 __sysvec_call_function+0x18/0xc0 sysvec_call_function+0x69/0x90 </IRQ> <TASK> asm_sysvec_call_function+0x16/0x20 RIP: 0010:cpuidle_enter_state+0xc4/0x450 ? cpuidle_enter_state+0xb7/0x450 cpuidle_enter+0x29/0x40 cpuidle_idle_call+0xf5/0x160 do_idle+0x7b/0xe0 cpu_startup_entry+0x26/0x30 start_secondary+0x115/0x140 secondary_startup_64_no_verify+0x194/0x19b </TASK> Fix this by ensuring that BRS is not enabled from the event selector reprogramming path even when cpuc->lbr_users > 0.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ bae19fdd7e9e759580ac4693d2df3bc23ab415d7 and < e9b1a7411a667539c2f55e720bbb5f623b526a32≥ bae19fdd7e9e759580ac4693d2df3bc23ab415d7 and < 7cc438c99bba324a0562b1bafa747b10f7e251df≥ bae19fdd7e9e759580ac4693d2df3bc23ab415d7 and < 46d0fd8535edce31f15e48d2de1bdee39a4850e5≥ bae19fdd7e9e759580ac4693d2df3bc23ab415d7 and < 07c60dda9c059c09f83d42a3ebda2e7cc1cf3bc2version 5.19≥ bae19fdd7e9e759580ac4693d2df3bc23ab415d7 and < 3b0aa139ba09a5b73c0f300e652076232f869f68≥ bae19fdd7e9e759580ac4693d2df3bc23ab415d7 and < cb5322d04694d153cd5418267f8765a44b935f82 | Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 15, 2026 → Oct 29, 2026 · 14 reading(s) · max 0.21%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Affected products added · linux/linux
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 3× References added · Oct 21, 2026 – Oct 30, 2026
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- git.kernel.org/stable/c/e9b1a7411a667539c2f55e720bbb5f623b526a32
- git.kernel.org/stable/c/7cc438c99bba324a0562b1bafa747b10f7e251df
- git.kernel.org/stable/c/46d0fd8535edce31f15e48d2de1bdee39a4850e5
- git.kernel.org/stable/c/07c60dda9c059c09f83d42a3ebda2e7cc1cf3bc2
- github.com/advisories/GHSA-522h-ffm3-c569
- git.kernel.org/stable/c/cb5322d04694d153cd5418267f8765a44b935f82
- git.kernel.org/stable/c/3b0aa139ba09a5b73c0f300e652076232f869f68
- nvd.nist.gov/vuln/detail/CVE-2026-72325
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
- Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
- Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
- Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
- Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
- Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-72325 is "perf/x86/amd/core: Avoid enabling BRS from the SVM reload path", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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