CyberSecBulletin
CVE-2024-26988NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2024-26988 is a high-severity out-of-bounds write 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 2ef607ea103616aec0289f1b65d103d499fa903a, 0dc727a4e05400205358a22c3d01ccad2c8e1fe4, 76c2f4d426a5358fced5d5990744d46f10a4ccea 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 0.28% 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 2ef607ea103616aec0289f1b65d103d499fa903a or 0dc727a4e05400205358a22c3d01ccad2c8e1fe4 or 76c2f4d426a5358fced5d5990744d46f10a4ccea or 81cf85ae4f2dd5fa3e43021782aa72c4c85558e8, whichever matches your release line, or a later version.
  2. Update RUGGEDCOM RST2428P to V3.1 or a later version.
  3. Update SCALANCE XCM-/XRM-/XCH-/XRH-300 family to V3.1 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxf5c7310ac73ea270e3a1acdb73d1b4817f11fd67 up to, but not including, 2ef607ea103616aec0289f1b65d103d499fa903a; f5c7310ac73ea270e3a1acdb73d1b4817f11fd67 up to, but not including, 0dc727a4e05400205358a22c3d01ccad2c8e1fe4; f5c7310ac73ea270e3a1acdb73d1b4817f11fd67 up to, but not including, 76c2f4d426a5358fced5d5990744d46f10a4ccea; f5c7310ac73ea270e3a1acdb73d1b4817f11fd67 up to, but not including, 81cf85ae4f2dd5fa3e43021782aa72c4c85558e8; f5c7310ac73ea270e3a1acdb73d1b4817f11fd67 up to, but not including, 936a02b5a9630c5beb0353c3085cc49d86c57034; f5c7310ac73ea270e3a1acdb73d1b4817f11fd67 up to, but not including, 46dad3c1e57897ab9228332f03e1c14798d2d3b9; 5.12ef607ea103616aec0289f1b65d103d499fa903a, 0dc727a4e05400205358a22c3d01ccad2c8e1fe4, 76c2f4d426a5358fced5d5990744d46f10a4ccea, 81cf85ae4f2dd5fa3e43021782aa72c4c85558e8, 936a02b5a9630c5beb0353c3085cc49d86c57034, 46dad3c1e57897ab9228332f03e1c14798d2d3b9
SiemensRUGGEDCOM RST2428Pbefore V3.1V3.1
SiemensSCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 familyNot specified in the recordNot stated
SiemensSCALANCE XCM-/XRM-/XCH-/XRH-300 familybefore V3.1V3.1
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystembefore V1.1.1V1.1.1
LinuxLinux Kernel5.1 up to, but not including, 5.10.216; 5.11 up to, but not including, 5.15.157; 5.16 up to, but not including, 6.1.88; 6.2 up to, but not including, 6.6.29; 6.7 up to, but not including, 6.8.8; 6.95.10.216, 5.15.157, 6.1.88, 6.6.29, 6.8.8
DebianDebian Linux10.0Not stated
Fedora ProjectFedora38; 39; 40Not 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.

Official description

In the Linux kernel, the following vulnerability has been resolved: init/main.c: Fix potential static_command_line memory overflow We allocate memory of size 'xlen + strlen(boot_command_line) + 1' for static_command_line, but the strings copied into static_command_line are extra_command_line and command_line, rather than extra_command_line and boot_command_line. When strlen(command_line) > strlen(boot_command_line), static_command_line will overflow. This patch just recovers strlen(command_line) which was miss-consolidated with strlen(boot_command_line) in the commit f5c7310ac73e ("init/main: add checks for the return value of memblock_alloc*()")

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

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

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 Out-of-bounds Write vulnerabilities

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