CyberSecBulletin
CVE-2026-64106NVD status: Modified

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its…

Published Updated By the CyberSecBulletin desk

CVE-2026-64106 is a critical-severity improper input validation vulnerability in Linux, with a CVSS 3.1 base score of 9.0 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. The record lists versions 1716b7fea2ead941a0dfac06c4504a3437cdf00d, dab9f93251b2c86a033de6098d0c73afddd55d4a, b94538186a3eae3763b8f96dacd610920a865aa7 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.15% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Linux to 1716b7fea2ead941a0dfac06c4504a3437cdf00d or dab9f93251b2c86a033de6098d0c73afddd55d4a or b94538186a3eae3763b8f96dacd610920a865aa7 or 0680f511926589206f81f57f76ce131d7741a316, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.1.175 or 6.6.142 or 6.12.92 or 6.18.34, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux57a9a117154c93539e33161dd318e6aeb8c04efa up to, but not including, 1716b7fea2ead941a0dfac06c4504a3437cdf00d; 57a9a117154c93539e33161dd318e6aeb8c04efa up to, but not including, dab9f93251b2c86a033de6098d0c73afddd55d4a; 57a9a117154c93539e33161dd318e6aeb8c04efa up to, but not including, b94538186a3eae3763b8f96dacd610920a865aa7; 57a9a117154c93539e33161dd318e6aeb8c04efa up to, but not including, 0680f511926589206f81f57f76ce131d7741a316; 57a9a117154c93539e33161dd318e6aeb8c04efa up to, but not including, 8bcd15b690a390241179516af1b6ae49ebfd9d95; 57a9a117154c93539e33161dd318e6aeb8c04efa up to, but not including, 9ce754ed8e7ab4e3999767ce1505f85c449ccb07; 4.121716b7fea2ead941a0dfac06c4504a3437cdf00d, dab9f93251b2c86a033de6098d0c73afddd55d4a, b94538186a3eae3763b8f96dacd610920a865aa7, 0680f511926589206f81f57f76ce131d7741a316, 8bcd15b690a390241179516af1b6ae49ebfd9d95, 9ce754ed8e7ab4e3999767ce1505f85c449ccb07
LinuxLinux Kernel4.12 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.142; 6.7 up to, but not including, 6.12.92; 6.13 up to, but not including, 6.18.34; 6.19 up to, but not including, 7.0.11; 7.16.1.175, 6.6.142, 6.12.92, 6.18.34, 7.0.11

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid_bits Userspace can restore an ITS Device Table Entry whose Size field encodes more EventID bits than the virtual ITS supports. The live MAPD path rejects that state, but vgic_its_restore_dte() accepts it and stores the out-of-range value in dev->num_eventid_bits. Reject restored DTEs with num_eventid_bits > VITS_TYPER_IDBITS before allocating the device. This mirrors the MAPD check and prevents the restored state from reaching vgic_its_restore_itt(), where the unchecked value can be converted into an oversized scan_its_table() range.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How developers prevent this class of flaw

  • Consider using language-theoretic security (LangSec) techniques that characterize inputs using a formal language and build recognizers for that language. This effectively requires parsing to be a distinct layer that effectively enforces a boundary between raw input and internal data representations, instead of allowing parser code to be scattered throughout the program, where it could be subject to errors or inconsistencies that create weaknesses.
  • Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
  • Understand all the potential areas where untrusted inputs can enter the product, including but not limited to: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.

More Improper Input Validation vulnerabilities (CWE-20)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Input Validation vulnerabilities

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