CyberSecBulletin
CVE-2023-53495NVD status: Modified

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2023-53495 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 ba6673824efa3dc198b04a54e69dce480066d7d9, 61054a8ddb176b155a8f2bacdfefb3727187f5d9, 5bb09dddc724c5f7c4dc6dd3bfebd685eecd93e8 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 0.17% 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 ba6673824efa3dc198b04a54e69dce480066d7d9 or 61054a8ddb176b155a8f2bacdfefb3727187f5d9 or 5bb09dddc724c5f7c4dc6dd3bfebd685eecd93e8 or 349638f7e5d3c7d328565587bb7b0454bbee02e2, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.4.257 or 5.10.195 or 5.15.132 or 6.1.54, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux90b509b39ac9b09be88eb641c7a3abd8de06b698 up to, but not including, ba6673824efa3dc198b04a54e69dce480066d7d9; 90b509b39ac9b09be88eb641c7a3abd8de06b698 up to, but not including, 61054a8ddb176b155a8f2bacdfefb3727187f5d9; 90b509b39ac9b09be88eb641c7a3abd8de06b698 up to, but not including, 5bb09dddc724c5f7c4dc6dd3bfebd685eecd93e8; 90b509b39ac9b09be88eb641c7a3abd8de06b698 up to, but not including, 349638f7e5d3c7d328565587bb7b0454bbee02e2; 90b509b39ac9b09be88eb641c7a3abd8de06b698 up to, but not including, 625b70d31dd4df4b96b3ddcbe251debb33bd67f5; 90b509b39ac9b09be88eb641c7a3abd8de06b698 up to, but not including, 51fe0a470543f345e3c62b6798929de3ddcedc1d; 5.2ba6673824efa3dc198b04a54e69dce480066d7d9, 61054a8ddb176b155a8f2bacdfefb3727187f5d9, 5bb09dddc724c5f7c4dc6dd3bfebd685eecd93e8, 349638f7e5d3c7d328565587bb7b0454bbee02e2, 625b70d31dd4df4b96b3ddcbe251debb33bd67f5, 51fe0a470543f345e3c62b6798929de3ddcedc1d
LinuxLinux Kernel5.2 up to, but not including, 5.4.257; 5.5 up to, but not including, 5.10.195; 5.11 up to, but not including, 5.15.132; 5.16 up to, but not including, 6.1.54; 6.2 up to, but not including, 6.5.4; 6.65.4.257, 5.10.195, 5.15.132, 6.1.54, 6.5.4

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

Official description

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mvpp2_main: fix possible OOB write in mvpp2_ethtool_get_rxnfc() rules is allocated in ethtool_get_rxnfc and the size is determined by rule_cnt from user space. So rule_cnt needs to be check before using rules to avoid OOB writing or NULL pointer dereference.

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

References

Recent Out-of-bounds Write vulnerabilities

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