CyberSecBulletin
CVE-2023-34195NVD status: Modified

Insydeh2o: Improper Control of Generation of Code

Published Updated By the CyberSecBulletin desk

CVE-2023-34195 is a high-severity improper control of generation of code vulnerability in Insydeh2o from Insyde, 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 5.2.05.28.22, 5.3.05.37.22, 5.4.05.45.22 as the first without the flaw, so updating Insydeh2o to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.23% 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 Insydeh2o to 5.2.05.28.22 or 5.3.05.37.22 or 5.4.05.45.22 or 5.5.05.53.22, whichever matches your release line, or a later version.
  2. Read the advisory on insyde.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
InsydeInsydeh2o5.2 up to, but not including, 5.2.05.28.22; 5.3 up to, but not including, 5.3.05.37.22; 5.4 up to, but not including, 5.4.05.45.22; 5.5 up to, but not including, 5.5.05.53.22; 5.6 up to, but not including, 5.6.05.60.225.2.05.28.22, 5.3.05.37.22, 5.4.05.45.22, 5.5.05.53.22, 5.6.05.60.22

Version data comes from NVD's product matching. 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.

Official description

An issue was discovered in SystemFirmwareManagementRuntimeDxe in Insyde InsydeH2O with kernel 5.0 through 5.5. The implementation of the GetImage method retrieves the value of a runtime variable named GetImageProgress, and later uses this value as a function pointer. This variable is wiped out by the same module near the end of the function. By setting this UEFI variable from the OS to point into custom code, an attacker could achieve arbitrary code execution in the DXE phase, before several chipset locks are set.

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

The underlying weakness: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

How developers prevent this class of flaw

  • Refactor your program so that you do not have to dynamically generate code.
  • Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
  • Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

More Improper Control of Generation of Code vulnerabilities (CWE-94)

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 Insydeh2o

All Insydeh2o vulnerabilities

Recent Improper Control of Generation of Code vulnerabilities

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