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CVE-2026-98616

Microsoft — eth: fbnic: reset num_napi when the napi vectors are freed

Microsoft · Not classified by connected sources

Patch Tuesday
0

EVRS 0 of 100 Informational

Monitor

Rank 2,921 of 2,960 tracked

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Why it scores 0

Evidence available: 2 of 8 signals

No strong exploitation, disclosure, or severity signal is available for this CVE yet.

  • CISA KEVDid not apply
  • RansomwareNo data
  • Vendor exploitationNo data
  • EPSSDid not apply
  • Microsoft Exploitability IndexNo data
  • Pre-patch disclosureNo data
  • KEV recencyNo data
  • CVSSNo data

The band answers “how soon”, not “how bad”. No data for: Ransomware, Vendor exploitation, Microsoft Exploitability Index, Pre-patch disclosure, KEV recency, CVSS. Why some signals show no data

Fix

No fixed version identified yet

Affected versions

Not identified by the connected sources

Remediation

NVD lists one or more references for this CVE that aren't tagged as a patch or vendor advisory. Review them directly to confirm patch availability and applicability before making a remediation decision.

Evidence

Each value with its source
MeasureValueSource
CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. Not publishedNVD and the CVE record were checked and hold no score. NVD
FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. 0.002 (5.5th pctl) FIRST EPSS
Actively exploitedWhether a source of record has confirmed attacks using it in the wild. Not confirmed Patch Tuesday
Public exploit moduleA module existing is not the same as active exploitation. None known Metasploit
EUVD cross-referenceENISA's record: CVSS 0.0, assigned by Linux. Listed ENISA EUVD

Description

NVD

In the Linux kernel, the following vulnerability has been resolved: eth: fbnic: reset num_napi when the napi vectors are freed fbn->num_napi is the count of live napi vectors, each of which owns an IRQ. The PM path had freed them without clearing the count. fbnic_pm_suspend() tears the datapath down via ndo_stop() and frees the IRQs, but leaves netif_running() true so resume knows to re-open. Resume rebuilds the datapath in __fbnic_pm_resume() and fbnic_reset_queues() sets num_napi and __fbnic_open() re-allocates the vectors. When the datapath is torn down but never rebuilt, num_napi is left pointing at freed vectors under 2 different scenarios: - a PCIe error recovery that fails (fbnic_err_slot_reset() -> __fbnic_pm_resume() returns an error -> PCI_ERS_RESULT_DISCONNECT), so .resume never runs; or - an __fbnic_open() that fails partway on resume and unwinds, freeing the vectors after fbnic_reset_queues() has already set num_napi. The netdev is then running with num_napi > 0 but napi[] freed, and the eventual remove/unbind close re-enters fbnic_down() -> fbnic_dbg_down() and dereferences the freed vectors: BUG: kernel NULL pointer dereference, address: 0000000000000210 RIP: fbnic_dbg_down+0x28 Clear num_napi when the vectors are freed: in the suspend teardown (a good resume re-establishes it before __fbnic_open()) and on the resume open failure. A redundant ndo_stop() then walks an empty napi[]. The normal ndo_stop() down/up cycle is untouched and keeps num_napi for the next ndo_open().