CyberSecBulletin
CVE-2022-31642NVD status: Modified

HP PC BIOS: Time-of-check Time-of-use (TOCTOU) Race Condition

CVE-2022-31642 is a high-severity time-of-check time-of-use (TOCTOU) race condition vulnerability in HP PC BIOS from HP, with a CVSS 3.1 base score of 7.0 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 HP PC BIOS versions: See HP Security Bulletin reference for affected versions.. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.14% 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 Elite Dragonfly Firmware to 01.21.01 or a later version.
  2. Update Elite Dragonfly G3 Firmware to 01.03.01 or 01.01.03, whichever matches your release line, or a later version.
  3. Update Elite X2 1012 G2 Firmware to 1.43 or a later version.
  4. Read the advisory on support.hp.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
HPHP PC BIOSSee HP Security Bulletin reference for affected versions.Not stated
HPElite Dragonfly Firmwarebefore 01.21.0101.21.01
HPElite Dragonfly G3 Firmwarebefore 01.03.01; before 01.01.0301.03.01, 01.01.03
HPElite X2 1012 G2 Firmwarebefore 1.431.43
HPElite X2 1013 G3 Firmwarebefore 01.21.0101.21.01
HPElite X2 G4 Firmwarebefore 01.21.0101.21.01
HPElite X360 1040 G9 Firmwarebefore 01.03.0101.03.01
HPElite X360 830 G9 Firmwarebefore 01.03.0101.03.01
HPElitebook 1040 G9 Firmwarebefore 01.03.0101.03.01
HPElitebook 1040 G4 Firmwarebefore 1.431.43
HPElitebook 1050 G1 Firmwarebefore 01.21.0201.21.02
HPElitebook 630 G9 Firmwarebefore 01.04.0001.04.00
HPElitebook 640 G9 Firmwarebefore 01.04.0001.04.00
HPElitebook 645 G9 Firmwarebefore 01.08.0101.08.01
HPElitebook 650 G9 Firmwarebefore 01.04.0001.04.00
HPElitebook 655 G9 Firmwarebefore 01.08.0101.08.01
HPElitebook 725 G4 Firmwarebefore 1.421.42
HPElitebook 735 G5 Firmwarebefore 01.21.0101.21.01
HPElitebook 735 G6 Firmwarebefore 01.21.0101.21.01
HPElitebook 745 G4 Firmwarebefore 1.421.42
HPElitebook 745 G5 Firmwarebefore 01.21.0101.21.01
HPElitebook 745 G6 Firmwarebefore 01.21.0101.21.01
HPElitebook 755 G4 Firmwarebefore 1.421.42
HPElitebook 755 G5 Firmwarebefore 01.21.0101.21.01
HPElitebook 820 G4 Firmwarebefore 1.431.43

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
HighSuccess depends on conditions outside the attacker's control.
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:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.0HighNVD
CVSS 3.17.0HighCISA (ADP)

Official description

Potential vulnerabilities have been identified in the system BIOS of certain HP PC products, which might allow arbitrary code execution, escalation of privilege, denial of service, and information disclosure.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Time-of-check Time-of-use (TOCTOU) Race Condition

The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.

How developers prevent this class of flaw

  • The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
  • When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
  • Limit the interleaving of operations on files from multiple processes.

More Time-of-check Time-of-use (TOCTOU) Race Condition vulnerabilities (CWE-367)

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 HP PC BIOS

All HP PC BIOS vulnerabilities

Recent Time-of-check Time-of-use (TOCTOU) Race Condition vulnerabilities

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