CyberSecBulletin
CVE-2026-64330NVD status: Analyzed

Linux: Improper Validation of Array Index

Published Updated By the CyberSecBulletin desk

CVE-2026-64330 is a high-severity improper validation of array index vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 89ff289cbf5d3b659a2babc5ccaae4eaf7e7cf53, d638ec188e95fe60f4b01106ffd41958f8fb3c2c, f8163c414de8640f2ca82ce4dc93409d4cdc2fad 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 0.13% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 89ff289cbf5d3b659a2babc5ccaae4eaf7e7cf53 or d638ec188e95fe60f4b01106ffd41958f8fb3c2c or f8163c414de8640f2ca82ce4dc93409d4cdc2fad or 012406f89abc52d1d5f07aa5653b519ebf6d2407, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.261 or 5.15.212 or 6.1.178 or 6.6.145, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, 89ff289cbf5d3b659a2babc5ccaae4eaf7e7cf53; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, d638ec188e95fe60f4b01106ffd41958f8fb3c2c; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, f8163c414de8640f2ca82ce4dc93409d4cdc2fad; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, 012406f89abc52d1d5f07aa5653b519ebf6d2407; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, c6d2af3b217a525741c472f0ab45d7d274b8468f; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, 3e1b1ac47e8163627f159f30d80d51b914620dd4; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, 313ca06e7e224ca1dfadd5722fe71fb8bc276b8b; 4ab8c18d4d67321cc7b660559de17511d4fc0237 up to, but not including, 7b681dd5fbf60b24a13c14661e5b7735759fb491; and 1 more ranges89ff289cbf5d3b659a2babc5ccaae4eaf7e7cf53, d638ec188e95fe60f4b01106ffd41958f8fb3c2c, f8163c414de8640f2ca82ce4dc93409d4cdc2fad, 012406f89abc52d1d5f07aa5653b519ebf6d2407, c6d2af3b217a525741c472f0ab45d7d274b8468f, 3e1b1ac47e8163627f159f30d80d51b914620dd4
LinuxLinux Kernel4.19 up to, but not including, 5.10.261; 5.11 up to, but not including, 5.15.212; 5.16 up to, but not including, 6.1.178; 6.2 up to, but not including, 6.6.145; 6.7 up to, but not including, 6.12.96; 6.13 up to, but not including, 6.18.39; 6.19 up to, but not including, 7.1.4; 7.25.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39

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
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

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

Official description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: tcpm: Validate SVID index in svdm_consume_modes() In svdm_consume_modes(), the SVID value is read from pmdata->svids using pmdata->svid_index as an array index without bounds validation: paltmode->svid = pmdata->svids[pmdata->svid_index]; If pmdata->svid_index is driven beyond SVID_DISCOVERY_MAX (16), it results in an out-of-bounds read of the pmdata->svids array. Because pd_mode_data is embedded inside struct tcpm_port, indexing past svids reads into adjacent fields. In particular: - At index 16, it reads the altmodes count. - At index 18 and beyond, it reads into altmode_desc[], which contains partner-supplied SVDM Discovery Modes VDOs. By injecting a chosen SVID into altmode_desc[0].vdo and driving svid_index to 20, the partner can force paltmode->svid to be loaded with an arbitrary, partner- chosen SVID, which is then registered via typec_partner_register_altmode(). Fix this by validating that pmdata->svid_index is non-negative and strictly less than pmdata->nsvids before accessing the pmdata->svids array inside svdm_consume_modes().

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

The underlying weakness: Improper Validation of Array Index

The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.

How developers prevent this class of flaw

  • 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).
  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, Ada allows the programmer to constrain the values of a variable and languages such as Java and Ruby will allow the programmer to handle exceptions when an out-of-bounds index is accessed.
  • Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment. For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND.

More Improper Validation of Array Index vulnerabilities (CWE-129)

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 Validation of Array Index vulnerabilities

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