CyberSecBulletin
CVE-2022-40246NVD status: Modified

Aptio: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2022-40246 is a high-severity out-of-bounds write vulnerability in Aptio from AMI, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited with physical access to the device by an attacker with administrator privileges, without any action from a user. Affected Aptio versions: 5.x. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.49% 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. Check which version of Aptio you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on ami.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
AMIAptio5.xNot stated
IntelNuc M15 Laptop Kit Lapbc510 Firmware0072Not stated
IntelNuc M15 Laptop Kit Lapbc710 Firmware0072Not 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
PhysicalThe attacker must physically touch the device.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:P/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighNVD
CVSS 3.17.2HighCISA (ADP)

Official description

A potential attacker can write one byte by arbitrary address at the time of the PEI phase (only during S3 resume boot mode) and influence the subsequent boot stages. This can lead to the mitigations bypassing, physical memory contents disclosure, discovery of any secrets from any Virtual Machines (VMs) and bypassing memory isolation and confidential computing boundaries. Additionally, an attacker can build a payload which can be injected into the SMRAM memory. This issue affects: Module name: SbPei SHA256: d827182e5f9b7a9ff0b9d3e232f7cfac43b5237e2681e11f005be627a49283a9 Module GUID: c1fbd624-27ea-40d1-aa48-94c3dc5c7e0d

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: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in Aptio

All Aptio vulnerabilities

Recent Out-of-bounds Write vulnerabilities

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