CyberSecBulletin
CVE-2024-47751NVD status: Modified

Linux: Buffer Copy without Checking Size of Input

Published Updated By the CyberSecBulletin desk

CVE-2024-47751 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 a5f795f9412854df28e66679c5e6b68b0b79c229, 95248d7497bcbfe7deed4805469c6ff6ddd7f9d1, 6dcc5b49d6607a741a14122bf3105f3ac50d259e 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 0.23% 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 a5f795f9412854df28e66679c5e6b68b0b79c229 or 95248d7497bcbfe7deed4805469c6ff6ddd7f9d1 or 6dcc5b49d6607a741a14122bf3105f3ac50d259e or aeb0335971806e15ac91e838ca471936c8e7efd5, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.1.113 or 6.6.54 or 6.10.13 or 6.11.2, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxb22dbbb24571c052364f476381dbac110bdca4d5 up to, but not including, a5f795f9412854df28e66679c5e6b68b0b79c229; b22dbbb24571c052364f476381dbac110bdca4d5 up to, but not including, 95248d7497bcbfe7deed4805469c6ff6ddd7f9d1; b22dbbb24571c052364f476381dbac110bdca4d5 up to, but not including, 6dcc5b49d6607a741a14122bf3105f3ac50d259e; b22dbbb24571c052364f476381dbac110bdca4d5 up to, but not including, aeb0335971806e15ac91e838ca471936c8e7efd5; b22dbbb24571c052364f476381dbac110bdca4d5 up to, but not including, c500a86693a126c9393e602741e348f80f1b0fc5; 5.16a5f795f9412854df28e66679c5e6b68b0b79c229, 95248d7497bcbfe7deed4805469c6ff6ddd7f9d1, 6dcc5b49d6607a741a14122bf3105f3ac50d259e, aeb0335971806e15ac91e838ca471936c8e7efd5, c500a86693a126c9393e602741e348f80f1b0fc5
LinuxLinux Kernel5.16 up to, but not including, 6.1.113; 6.2 up to, but not including, 6.6.54; 6.7 up to, but not including, 6.10.13; 6.11 up to, but not including, 6.11.26.1.113, 6.6.54, 6.10.13, 6.11.2

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: PCI: kirin: Fix buffer overflow in kirin_pcie_parse_port() Within kirin_pcie_parse_port(), the pcie->num_slots is compared to pcie->gpio_id_reset size (MAX_PCI_SLOTS) which is correct and would lead to an overflow. Thus, fix condition to pcie->num_slots + 1 >= MAX_PCI_SLOTS and move pcie->num_slots increment below the if-statement to avoid out-of-bounds array access. Found by Linux Verification Center (linuxtesting.org) with SVACE. [kwilczynski: commit log]

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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