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CVE-2024-43842NVD status: Modified

Linux: Improper Validation of Array Index

CVE-2024-43842 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 a2a095c08b95372d6d0c5819b77f071af5e75366, 7a0edc3d83aff3a48813d78c9cad9daf38decc74, 96ae4de5bc4c8ba39fd072369398f59495b73f58 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 0.22% 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 a2a095c08b95372d6d0c5819b77f071af5e75366 or 7a0edc3d83aff3a48813d78c9cad9daf38decc74 or 96ae4de5bc4c8ba39fd072369398f59495b73f58 or 85099c7ce4f9e64c66aa397cd9a37473637ab891, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.1.103 or 6.6.44 or 6.10.3, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxe3ec7017f6a20d12ddd9fe23d345ebb7b8c104dd up to, but not including, a2a095c08b95372d6d0c5819b77f071af5e75366; e3ec7017f6a20d12ddd9fe23d345ebb7b8c104dd up to, but not including, 7a0edc3d83aff3a48813d78c9cad9daf38decc74; e3ec7017f6a20d12ddd9fe23d345ebb7b8c104dd up to, but not including, 96ae4de5bc4c8ba39fd072369398f59495b73f58; e3ec7017f6a20d12ddd9fe23d345ebb7b8c104dd up to, but not including, 85099c7ce4f9e64c66aa397cd9a37473637ab891; 5.16a2a095c08b95372d6d0c5819b77f071af5e75366, 7a0edc3d83aff3a48813d78c9cad9daf38decc74, 96ae4de5bc4c8ba39fd072369398f59495b73f58, 85099c7ce4f9e64c66aa397cd9a37473637ab891
LinuxLinux Kernel5.16 up to, but not including, 6.1.103; 6.2 up to, but not including, 6.6.44; 6.7 up to, but not including, 6.10.36.1.103, 6.6.44, 6.10.3

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: wifi: rtw89: Fix array index mistake in rtw89_sta_info_get_iter() In rtw89_sta_info_get_iter() 'status->he_gi' is compared to array size. But then 'rate->he_gi' is used as array index instead of 'status->he_gi'. This can lead to go beyond array boundaries in case of 'rate->he_gi' is not equal to 'status->he_gi' and is bigger than array size. Looks like "copy-paste" mistake. Fix this mistake by replacing 'rate->he_gi' with 'status->he_gi'. Found by Linux Verification Center (linuxtesting.org) with SVACE.

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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