CyberSecBulletin
CVE-2024-38577NVD status: Modified

Linux: Buffer Copy without Checking Size of Input

Published Updated By the CyberSecBulletin desk

CVE-2024-38577 is a high-severity buffer copy without checking size of input 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 17c43211d45f13d1badea3942b76bf16bcc49281, af7b560c88fb420099e29890aa682b8a3efc8784, 08186d0c5fb64a1cc4b43e009314ee6b173ed222 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 17c43211d45f13d1badea3942b76bf16bcc49281 or af7b560c88fb420099e29890aa682b8a3efc8784 or 08186d0c5fb64a1cc4b43e009314ee6b173ed222 or 32d988f48ed287e676a29a15ac30701c35849aec, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.226 or 5.15.167 or 6.1.93 or 6.6.33, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxedf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, 17c43211d45f13d1badea3942b76bf16bcc49281; edf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, af7b560c88fb420099e29890aa682b8a3efc8784; edf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, 08186d0c5fb64a1cc4b43e009314ee6b173ed222; edf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, 32d988f48ed287e676a29a15ac30701c35849aec; edf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, 6593d857ce5b5b802fb73d8091ac9c84b92c1697; edf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, 1a240e138071b25944ded0f5b3e357aa99fabcb7; edf3775f0ad66879796f594983163f672c4bf1a2 up to, but not including, cc5645fddb0ce28492b15520306d092730dffa48; 5.817c43211d45f13d1badea3942b76bf16bcc49281, af7b560c88fb420099e29890aa682b8a3efc8784, 08186d0c5fb64a1cc4b43e009314ee6b173ed222, 32d988f48ed287e676a29a15ac30701c35849aec, 6593d857ce5b5b802fb73d8091ac9c84b92c1697, 1a240e138071b25944ded0f5b3e357aa99fabcb7
LinuxLinux Kernel5.8 up to, but not including, 5.10.226; 5.11 up to, but not including, 5.15.167; 5.16 up to, but not including, 6.1.93; 6.2 up to, but not including, 6.6.33; 6.7 up to, but not including, 6.8.12; 6.9 up to, but not including, 6.9.35.10.226, 5.15.167, 6.1.93, 6.6.33, 6.8.12, 6.9.3

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.

Scoring systemScoreSeverityScored by
CVSS 3.17.0HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: rcu-tasks: Fix show_rcu_tasks_trace_gp_kthread buffer overflow There is a possibility of buffer overflow in show_rcu_tasks_trace_gp_kthread() if counters, passed to sprintf() are huge. Counter numbers, needed for this are unrealistically high, but buffer overflow is still possible. Use snprintf() with buffer size instead of sprintf(). 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: Buffer Copy without Checking Size of Input

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output 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 Buffer Copy without Checking Size of Input vulnerabilities (CWE-120)

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 Buffer Copy without Checking Size of Input vulnerabilities

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