NVD / CVE Program· CNA Linux

CVE-2026-64524: drm/hyperv: validate resolution_count and fix WIN8 fallback

Noroxi assessment

Priority: Monitor (action score 30/100)

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: 0.14% (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 13d33b9ef67066c77c84273fac5a1d3fde3533d1, 1fb565b77b8f44afabb02de6310065f109d89e94, 8a114b25b5521eae451b13bce98ae978624962e5.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 13d33b9ef67066c77c84273fac5a1d3fde3533d1, 1fb565b77b8f44afabb02de6310065f109d89e94, 8a114b25b5521eae451b13bce98ae978624962e5 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: drm/hyperv: validate resolution_count and fix WIN8 fallback A SYNTHVID_RESOLUTION_RESPONSE with resolution_count > 64 walks past the supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT] array in the parse loop. Bound resolution_count against the array size, folded into the existing zero-check. When the WIN10 resolution probe fails, the caller in hyperv_connect_vsp() left hv->screen_*_max / preferred_* unpopulated, which sets mode_config.max_width / max_height to 0 and makes drm_internal_framebuffer_create() reject every userspace framebuffer with -EINVAL. The pre-WIN10 branch had the same gap for preferred_width / preferred_height. Use a single post-probe fallback guarded by screen_width_max == 0 so both paths converge on the WIN8 defaults.

HighCVSS 7.7 · v3.1—No exploit Fix available

Memory safety

Published: Jul 25, 2026
Updated: Nov 3, 2026
EPSS: 0.1% · 3th percentile
CWE: CWE-122

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.7 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.1%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · Linux: 7.7; 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.

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Affected 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.

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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
- 5.14affected
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before 96f7de3172d4aa878b7f87173b2b3507c350fcd6affected · git
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before bc573752f3dac0d1ab8df7078c1851bc76717653affected · git
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before 1fb565b77b8f44afabb02de6310065f109d89e94affected · git
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before a321c908f2eeea01539668eb270d074d9b88e490affected · git
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before 9c698b2c43c2667c34f5336bf46ad5786216ac2aaffected · git
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before 8a114b25b5521eae451b13bce98ae978624962e5affected · git
- 76c56a5affeba1e163b66b9d8cc192e6154466f0 and later · before 13d33b9ef67066c77c84273fac5a1d3fde3533d1affected · git
- before 5.14not affected · semver
- 5.15.210 and later · up to and including 5.15.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.176-1	6.1.176-1
Debian:13	linux	before 6.12.94-1	6.12.94-1
Debian:14	linux	before 7.0.12-1	7.0.12-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation
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CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment
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CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()
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Published before and after this one in the same product

← EarlierCVE-2026-64522Jul 25, 2026 · net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA
35Monitor
← EarlierCVE-2026-64523Jul 25, 2026 · net/handshake: Take a long-lived file reference at submit
39Monitor
Later →CVE-2026-64525Jul 25, 2026 · xfrm: move policy_bydst RCU sync from per-netns .exit to .pre_exit
0Monitor

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	13d33b9ef67066c77c84273fac5a1d3fde3533d1	Vendor (CNA)
Linux Linux	1fb565b77b8f44afabb02de6310065f109d89e94	Vendor (CNA)
Linux Linux	8a114b25b5521eae451b13bce98ae978624962e5	Vendor (CNA)
Linux Linux	96f7de3172d4aa878b7f87173b2b3507c350fcd6	Vendor (CNA)
Linux Linux	9c698b2c43c2667c34f5336bf46ad5786216ac2a	Vendor (CNA)
Linux Linux	a321c908f2eeea01539668eb270d074d9b88e490	Vendor (CNA)
Linux Linux	bc573752f3dac0d1ab8df7078c1851bc76717653	Vendor (CNA)
debian:linux	6.1.176-1 · Debian:12	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.

EPSS, last 120 days

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 researchers

Finders, 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.

CVE-2026-645584 days aparts390/pkey: Check length in pkey_pckmo handler implementation
31Monitor
CVE-2026-23178161 days apartHID: i2c-hid: fix potential buffer overflow in i2c_hid_get_report()
31Monitor
CVE-2025-68795193 days apartethtool: Avoid overflowing userspace buffer on stats query
31Monitor
CVE-2026-6829316 days apartnet/mlx5: Fix MCIA register buffer overflow on 32 dword reads
28Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

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Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).