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CVE-2022-32491NVD status: Modified

CPG BIOS: Buffer Copy without Checking Size of Input

CVE-2022-32491 is a high-severity buffer copy without checking size of input vulnerability in CPG BIOS from Dell, 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 version OptiPlex 7770 All-In-One BIOS (version: 1.14.0) as the first without the flaw, so updating CPG BIOS to that release 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 CPG BIOS to OptiPlex 7770 All-In-One BIOS (version: 1.14.0) or a later version.
  2. Update Alienware Area 51m R1 Firmware to 1.21.0 or a later version.
  3. Update Alienware Area 51m R2 Firmware to 1.18.0 or a later version.
  4. Read the advisory on dell.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
DellCPG BIOSbefore OptiPlex 7770 All-In-One BIOS (version: 1.14.0)OptiPlex 7770 All-In-One BIOS (version: 1.14.0)
DellAlienware Area 51m R1 Firmwarebefore 1.21.01.21.0
DellAlienware Area 51m R2 Firmwarebefore 1.18.01.18.0
DellAlienware Aurora R11 Firmwarebefore 1.0.161.0.16
DellAlienware Aurora R12 Firmwarebefore 1.1.161.1.16
DellAlienware Aurora R13 Firmwarebefore 1.5.01.5.0
DellAlienware Aurora R10 Firmwarebefore 2.3.12.3.1
DellAlienware Aurora R8 Firmwarebefore 1.0.231.0.23
DellAlienware Aurora R9 Firmwarebefore 1.0.201.0.20
DellAlienware M15 R1 Firmwarebefore 2.14.02.14.0
DellAlienware M15 R2 Firmwarebefore 1.17.01.17.0
DellAlienware M15 R3 Firmwarebefore 1.19.01.19.0
DellAlienware M15 R4 Firmwarebefore 1.13.01.13.0
DellAlienware M17 R1 Firmwarebefore 2.14.02.14.0
DellAlienware M17 R2 Firmwarebefore 1.17.01.17.0
DellAlienware M17 R3 Firmwarebefore 1.19.01.19.0
DellAlienware M17 R4 Firmwarebefore 1.13.01.13.0
DellAlienware X14 Firmwarebefore 1.5.01.5.0
DellAlienware X15 R1 Firmwarebefore 1.11.01.11.0
DellAlienware X15 R2 Firmwarebefore 1.7.01.7.0
DellAlienware X17 R1 Firmwarebefore 1.11.01.11.0
DellAlienware X17 R2 Firmwarebefore 1.7.01.7.0
DellChengming 3980 Firmwarebefore 2.24.02.24.0
DellChengming 3988 Firmwarebefore 1.11.01.11.0
DellChengming 3990 Firmwarebefore 1.14.01.14.0

Version data comes from the organisation that assigned the CVE; 35 further products are omitted here. 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 3.14.1MediumCNA (emc.com)
CVSS 3.17.8HighNVD

Official description

Dell Client BIOS contains a Buffer Overflow vulnerability. A local authenticated malicious user may potentially exploit this vulnerability by manipulating an SMI to cause an arbitrary write during SMM.

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

Other vulnerabilities in CPG BIOS

All CPG BIOS vulnerabilities

Recent Buffer Copy without Checking Size of Input vulnerabilities

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