VulnerabilityPublished 6 Aug 2026Updated 11 Sep 2026

CVE-2026-64592: Linux kernel · riscv: mm: Unconditionally sfence.vma for spurious fault

Affects Linux kernelSource GCVE Database

Not known to be exploited · fixed in 7.0.0-1012.12~24.04.1 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 15:59 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 7.0.0-1012.12~24.04.1, 7.0.0-1011.11~24.04.1, 7.0.0-31.31~24.04.1 +7

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-m6hv-9h66-mmjv

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
Ubuntu 26.04 LTSlinux`pkg:deb/ubuntu/linux?arch=source&distro=resolute`Other threats	Affected <7.0.0-31.31	Fixed in 7.0.0-31.31
Ubuntu 26.04 LTSlinux-aws`pkg:deb/ubuntu/linux-aws?arch=source&distro=resolute`Other threats	Affected <7.0.0-1012.12	Fixed in 7.0.0-1012.12
Ubuntu 26.04 LTSlinux-azure`pkg:deb/ubuntu/linux-azure?arch=source&distro=resolute`Other threats	Affected 6.17.0-1003.3 – 7.0.0-1012.12 13 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-azure-fde`pkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resolute`Other threats	Affected 7.0.0-1003.3 – 7.0.0-1011.11 7 affected builds	Fixed in–
Ubuntu 26.04 LTSlinux-gcp`pkg:deb/ubuntu/linux-gcp?arch=source&distro=resolute`Other threats	Affected <7.0.0-1011.11	Fixed in 7.0.0-1011.11
Ubuntu 26.04 LTSlinux-gke`pkg:deb/ubuntu/linux-gke?arch=source&distro=resolute`Other threats	Affected <7.0.0-1006.7	Fixed in 7.0.0-1006.7

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A patch is available and should be applied by updating to the Linux kernel versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-1011.11, or 7.0.0-1012.12 (and related variants) as specified in the Ubuntu security advisories USN-8726-1 and USN-8727-1. After updating, a system reboot is required. Due to ABI changes, all third-party kernel modules must be recompiled and reinstalled. Users should follow the vendor's update instructions carefully to ensure full remediation.

Description

In the Linux kernel, the following vulnerability has been resolved: riscv: mm: Unconditionally sfence.vma for spurious fault Svvptc does not guarantee that it's safe to just return here. Since we have already cleared our bit, if, theoretically, the bounded timeframe for the accessed page to become valid still hasn't happened after sret, we could fault again and actually crash. Hopefully, these spurious faults should be rare enough that this is an acceptable slowdown.

Impact

If unpatched, this vulnerability could cause system instability or crashes on affected RISC-V systems due to repeated faults in memory management. While no known exploits are reported in the wild, the issue could potentially be leveraged to disrupt system operations. The broader kernel updates also address privilege escalation and memory protection bypass issues in other architectures, indicating a significant overall security improvement.

Summary

The Linux kernel vulnerability CVE-2026-64592 concerns the RISC-V architecture's memory management where unconditional sfence.vma execution for spurious faults does not ensure safe handling, potentially causing repeated faults and system crashes. This flaw was addressed in the Linux kernel 7.0 updates as part of a comprehensive security patch that also fixed multiple other vulnerabilities across various architectures and subsystems. The update requires users to upgrade to specific patched kernel versions and recompile any third-party kernel modules due to ABI changes.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 7 Sep 2026, 17:29 UTC

Technical details

References

Community reviews

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