CyberSecBulletin
CVE-2022-34403NVD status: Modified

CPG BIOS: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2022-34403 is a high-severity out-of-bounds write vulnerability in CPG BIOS from Dell, with a CVSS 3.1 base score of 8.8 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. Affected CPG BIOS versions: 2.15.2 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.18% 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 Alienware M15 R6 Firmware to 1.17.0 or a later version.
  2. Update Alienware M15 R7 Firmware to 1.4.3 or a later version.
  3. Update Alienware M15 Ryzen Edition R5 Firmware to 1.8.0 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 BIOS2.15.2 and earlierNot stated
DellAlienware M15 R6 Firmwarebefore 1.17.01.17.0
DellAlienware M15 R7 Firmwarebefore 1.4.31.4.3
DellAlienware M15 Ryzen Edition R5 Firmwarebefore 1.8.01.8.0
DellAlienware M17 R5 Amd Firmwarebefore 1.4.31.4.3
DellG15 5510 Firmwarebefore 1.16.01.16.0
DellG15 5511 Firmwarebefore 1.18.01.18.0
DellG15 5515 Firmwarebefore 1.8.01.8.0
DellG15 5525 Firmwarebefore 1.4.31.4.3
DellG5 Se 5505 Firmwarebefore 1.13.01.13.0
DellInspiron 14 5410 2-in-1 Firmwarebefore 2.15.22.15.2
DellInspiron 15 3511 Firmwarebefore 1.18.21.18.2
DellInspiron 3195 2-in-1 Firmwarebefore 1.6.01.6.0
DellInspiron 3275 Firmwarebefore 1.9.21.9.2
DellInspiron 3475 Firmwarebefore 1.9.21.9.2
DellInspiron 3505 Firmwarebefore 1.9.01.9.0
DellInspiron 3515 Firmwarebefore 1.9.01.9.0
DellInspiron 3525 Firmwarebefore 1.5.01.5.0
DellInspiron 3585 Firmwarebefore 1.10.01.10.0
DellInspiron 3595 Firmwarebefore 1.5.01.5.0
DellInspiron 3785 Firmwarebefore 1.10.01.10.0
DellInspiron 3891 Firmwarebefore 1.12.01.12.0
DellInspiron 5310 Firmwarebefore 2.15.02.15.0
DellInspiron 5405 Firmwarebefore 1.9.01.9.0
DellInspiron 5410 Firmwarebefore 2.14.02.14.0

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
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:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (emc.com)
CVSS 3.18.8HighNVD

Official description

Dell BIOS contains a Stack based buffer overflow vulnerability. A local authenticated attacker could potentially exploit this vulnerability by using an SMI to send larger than expected input to a parameter to gain arbitrary code execution in SMRAM.

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: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in CPG BIOS

All CPG BIOS vulnerabilities

Recent Out-of-bounds Write vulnerabilities

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