CyberSecBulletin
CVE-2025-38239NVD status: Modified

Linux: Improper Validation of Array Index

Published Updated By the CyberSecBulletin desk

CVE-2025-38239 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 f1064b3532192e987ab17be7281d5fee36fd25e1, bf2c1643abc3b2507d56bb6c22bf9897272f8a35, 19a47c966deb36624843b7301f0373a3dc541a05 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 0.18% 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 f1064b3532192e987ab17be7281d5fee36fd25e1 or bf2c1643abc3b2507d56bb6c22bf9897272f8a35 or 19a47c966deb36624843b7301f0373a3dc541a05 or 074efb35552556a4b3b25eedab076d5dc24a8199, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.1.143 or 6.6.96 or 6.12.36 or 6.15.5, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux8049da6f3943d0ac51931b8064b2e4769a69a967 up to, but not including, f1064b3532192e987ab17be7281d5fee36fd25e1; 8049da6f3943d0ac51931b8064b2e4769a69a967 up to, but not including, bf2c1643abc3b2507d56bb6c22bf9897272f8a35; 8049da6f3943d0ac51931b8064b2e4769a69a967 up to, but not including, 19a47c966deb36624843b7301f0373a3dc541a05; 8049da6f3943d0ac51931b8064b2e4769a69a967 up to, but not including, 074efb35552556a4b3b25eedab076d5dc24a8199; 8049da6f3943d0ac51931b8064b2e4769a69a967 up to, but not including, 752eb816b55adb0673727ba0ed96609a17895654; 5.17f1064b3532192e987ab17be7281d5fee36fd25e1, bf2c1643abc3b2507d56bb6c22bf9897272f8a35, 19a47c966deb36624843b7301f0373a3dc541a05, 074efb35552556a4b3b25eedab076d5dc24a8199, 752eb816b55adb0673727ba0ed96609a17895654
LinuxLinux Kernel5.17 up to, but not including, 6.1.143; 6.2 up to, but not including, 6.6.96; 6.7 up to, but not including, 6.12.36; 6.13 up to, but not including, 6.15.5; 6.166.1.143, 6.6.96, 6.12.36, 6.15.5
DebianDebian Linux11.0Not stated

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 3.17.3HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: scsi: megaraid_sas: Fix invalid node index On a system with DRAM interleave enabled, out-of-bound access is detected: megaraid_sas 0000:3f:00.0: requested/available msix 128/128 poll_queue 0 ------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in ./arch/x86/include/asm/topology.h:72:28 index -1 is out of range for type 'cpumask *[1024]' dump_stack_lvl+0x5d/0x80 ubsan_epilogue+0x5/0x2b __ubsan_handle_out_of_bounds.cold+0x46/0x4b megasas_alloc_irq_vectors+0x149/0x190 [megaraid_sas] megasas_probe_one.cold+0xa4d/0x189c [megaraid_sas] local_pci_probe+0x42/0x90 pci_device_probe+0xdc/0x290 really_probe+0xdb/0x340 __driver_probe_device+0x78/0x110 driver_probe_device+0x1f/0xa0 __driver_attach+0xba/0x1c0 bus_for_each_dev+0x8b/0xe0 bus_add_driver+0x142/0x220 driver_register+0x72/0xd0 megasas_init+0xdf/0xff0 [megaraid_sas] do_one_initcall+0x57/0x310 do_init_module+0x90/0x250 init_module_from_file+0x85/0xc0 idempotent_init_module+0x114/0x310 __x64_sys_finit_module+0x65/0xc0 do_syscall_64+0x82/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fix it accordingly.

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

Third-party and government advisories

Recent Improper Validation of Array Index vulnerabilities

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