CVE-2026-74573: iommu/arm-smmu-v3-iommufd: Require exactly one Stream ID for a vDEVICE
Noroxi assessment
Priority: Monitor (action score 37/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.13% (FIRST EPSS).
- Someone with local access to the system can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: Linux Linux 0acbc621341aca4eb94d9c2f43e1ab273ff088f0, 3808bab5d95ae79e333e11f6a73d178e084c645d, c3b8ee84a965058b41275069d4696f37a8b14bf6.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux 0acbc621341aca4eb94d9c2f43e1ab273ff088f0, 3808bab5d95ae79e333e11f6a73d178e084c645d, c3b8ee84a965058b41275069d4696f37a8b14bf6 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu-v3-iommufd: Require exactly one Stream ID for a vDEVICE arm_vsmmu_vsid_to_sid() maps a guest's vSID to a single physical Stream ID taken from master->streams[0], assuming a device has exactly one stream. A device with several streams gets only its first one mapped, so a guest vSID invalidation cannot reach the others' ATC and IOTLB entries; a device with none makes master->streams a ZERO_SIZE_PTR, read out of bounds. Add an arm_vsmmu_vdevice_init() op to reject the vDEVICE with -EOPNOTSUPP when master->num_streams is not one, rather than mapping it silently.
- Published
- Aug 15, 2026
- Updated
- Oct 16, 2026
- EPSS
- 0.1% · 2th percentile
- CWE
- —
Report tools
Action score
37
Monitor
Low priority for now.
- CVSS
- 37 / 40 · 9.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 9.3
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 6.13affected
- d68beb276ba26cec47350a6d468e967673ee0c56 and later · before 3808bab5d95ae79e333e11f6a73d178e084c645daffected · git
- d68beb276ba26cec47350a6d468e967673ee0c56 and later · before 0acbc621341aca4eb94d9c2f43e1ab273ff088f0affected · git
- d68beb276ba26cec47350a6d468e967673ee0c56 and later · before c3b8ee84a965058b41275069d4696f37a8b14bf6affected · git
- before 6.13not affected · semver
- 6.18.44 and later · up to and including 6.18.*not affected · semver
- 7.1.8 and later · up to and including 7.1.*not affected · semver
- 7.2 and laternot affected · original_commit_for_fix
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:14 | linux | before 7.1.8-1 | 7.1.8-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation40Plan
- CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment40Plan
- CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()40Plan
Published before and after this one in the same product
- ← EarlierCVE-2026-74571Aug 15, 2026 · btrfs: skip global block reserve accounting for rescue mounts0Monitor
- ← EarlierCVE-2026-74572Aug 15, 2026 · btrfs: zoned: fix deadlock between metadata writeback and transaction commit30Monitor
- Later →CVE-2026-74574Aug 15, 2026 · dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open()31Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 0acbc621341aca4eb94d9c2f43e1ab273ff088f0 | Vendor (CNA) |
| Linux Linux | 3808bab5d95ae79e333e11f6a73d178e084c645d | Vendor (CNA) |
| Linux Linux | c3b8ee84a965058b41275069d4696f37a8b14bf6 | Vendor (CNA) |
| debian:linux | 7.1.8-1 · Debian:14 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0854 · Aug 19, 2026(Linux Kernel Güvenlik Bildirimi)
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (2 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.