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CVE-2024-56596NVD status: Modified

Linux: Improper Validation of Array Index

CVE-2024-56596 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 b62f41aeec9d250144c53875b507c1d45ae8c8fc, 97e693593162eef6851d232f0c8148169ed46a5c, 9efe72eefd4c4a7ce63b3e4d667d766d2b360cb4 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 0.26% 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 b62f41aeec9d250144c53875b507c1d45ae8c8fc or 97e693593162eef6851d232f0c8148169ed46a5c or 9efe72eefd4c4a7ce63b3e4d667d766d2b360cb4 or ff9fc48fab0e1ea0d423c23c99b91bba178f0b05, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.4.287 or 5.10.231 or 5.15.174 or 6.1.120, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, b62f41aeec9d250144c53875b507c1d45ae8c8fc; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 97e693593162eef6851d232f0c8148169ed46a5c; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 9efe72eefd4c4a7ce63b3e4d667d766d2b360cb4; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, ff9fc48fab0e1ea0d423c23c99b91bba178f0b05; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, e7d376f94f72b020f84e77278b150ec1cc27502c; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 8ff7579554571d92e3deab168f5a7d7b146ed368; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 839f102efb168f02dfdd46717b7c6dddb26b015e; 2.6.12b62f41aeec9d250144c53875b507c1d45ae8c8fc, 97e693593162eef6851d232f0c8148169ed46a5c, 9efe72eefd4c4a7ce63b3e4d667d766d2b360cb4, ff9fc48fab0e1ea0d423c23c99b91bba178f0b05, e7d376f94f72b020f84e77278b150ec1cc27502c, 8ff7579554571d92e3deab168f5a7d7b146ed368
LinuxLinux Kernelbefore 5.4.287; 5.5 up to, but not including, 5.10.231; 5.11 up to, but not including, 5.15.174; 5.16 up to, but not including, 6.1.120; 6.2 up to, but not including, 6.6.66; 6.7 up to, but not including, 6.12.55.4.287, 5.10.231, 5.15.174, 6.1.120, 6.6.66, 6.12.5

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.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)

Official description

In the Linux kernel, the following vulnerability has been resolved: jfs: fix array-index-out-of-bounds in jfs_readdir The stbl might contain some invalid values. Added a check to return error code in that case.

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: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Validation of Array Index vulnerabilities

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