In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode
Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation
request when device is disconnected") relies on
pci_dev_is_disconnected() to skip ATS invalidation for
safely-removed devices, but it does not cover link-down caused
by faults, which can still hard-lock the system.
For example, if a VM fails to connect to the PCIe device,
"virsh destroy" is executed to release resources and isolate
the fault, but a hard-lockup occurs while releasing the group fd.
Call Trace:
qi_submit_sync
qi_flush_dev_iotlb
intel_pasid_tear_down_entry
device_block_translation
blocking_domain_attach_dev
__iommu_attach_device
__iommu_device_set_domain
__iommu_group_set_domain_internal
iommu_detach_group
vfio_iommu_type1_detach_group
vfio_group_detach_container
vfio_group_fops_release
__fput
Although pci_device_is_present() is slower than
pci_dev_is_disconnected(), it still takes only ~70 µs on a
ConnectX-5 (8 GT/s, x2) and becomes even faster as PCIe speed
and width increase.
Besides, devtlb_invalidation_with_pasid() is called only in the
paths below, which are far less frequent than memory map/unmap.
- mm-struct release
- {attach,release}_dev
- set/remove PASID
- dirty-tracking setup
The gain in system stability far outweighs the negligible cost
of using pci_device_is_present() instead of pci_dev_is_disconnected()
to decide when to skip ATS invalidation, especially under GDR
high-load conditions.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.1% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-05). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it