CVE-2026-64291

Local denial of service via oversized event queues

Published Jul 25, 2026 · Updated Jul 25, 2026

Resource exhaustion in affected Linux Kernel releases allows local users to interrupt service by allocating oversized iommufd event queues. iommufd_veventq_alloc accepts any nonzero userspace veventq_depth up to U32_MAX and sizes the queue without a practical upper bound. Low-privileged local access is required; exhausting kernel memory can deny service to the host without reported data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in affected Linux Kernel releases allows local users to interrupt service by allocating oversized iommufd event queues. iommufd_veventq_alloc accepts any nonzero userspace veventq_depth up to U32_MAX and sizes the queue without a practical upper bound. Low-privileged local access is required; exhausting kernel memory can deny service to the host without reported data disclosure or modification.

The record

CVE
CVE-2026-64291
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-770, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.15
  2. Affected versionversion=e36ba5ab808ef6237c3148d469c8238674230e2b <6ebf2eb46fbd5b40393ff8fbb847ba96925beaff
  3. Affected versionversion=e36ba5ab808ef6237c3148d469c8238674230e2b <e7b5e55652746b1221b9c10ff80eae8a154101ba
  4. Affected versionversion=e36ba5ab808ef6237c3148d469c8238674230e2b <f565297edf316016be4a1a9e2eb9f39359313f43

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=6.15; version=e36ba5ab808ef6237c3148d469c8238674230e2b <6ebf2eb46fbd5b40393ff8fbb847ba96925beaff; version=e36ba5ab808ef6237c3148d469c8238674230e2b <e7b5e55652746b1221b9c10ff80eae8a154101ba; version=e36ba5ab808ef6237c3148d469c8238674230e2b <f565297edf316016be4a1a9e2eb9f39359313f43

Published CVSS scores

5.5Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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