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CVE-2023-38298NVD status: Deferred

30Z_firmware: Incorrect Privilege Assignment

CVE-2023-38298 is a high-severity incorrect privilege assignment vulnerability in 30Z_firmware from Tcl, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. There is no confirmed exploitation so far. EPSS estimates a 0.45% 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 30Z_firmware you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Tcl30Z_firmwareNot specified in the recordNot 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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
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:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

Various software builds for the following TCL devices (30Z, A3X, 20XE, 10L) leak the device IMEI to a system property that can be accessed by any local app on the device without any permissions or special privileges. Google restricted third-party apps from directly obtaining non-resettable device identifiers in Android 10 and higher, but in these instances they are leaked by a high-privilege process and can be obtained indirectly. The software build fingerprints for each confirmed vulnerable device are as follows: TCL 30Z (TCL/4188R/Jetta_ATT:12/SP1A.210812.016/LV8E:user/release-keys, TCL/T602DL/Jetta_TF:12/SP1A.210812.016/vU5P:user/release-keys, TCL/T602DL/Jetta_TF:12/SP1A.210812.016/vU61:user/release-keys, TCL/T602DL/Jetta_TF:12/SP1A.210812.016/vU66:user/release-keys, TCL/T602DL/Jetta_TF:12/SP1A.210812.016/vU68:user/release-keys, TCL/T602DL/Jetta_TF:12/SP1A.210812.016/vU6P:user/release-keys, and TCL/T602DL/Jetta_TF:12/SP1A.210812.016/vU6X:user/release-keys); TCL A3X (TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vAAZ:user/release-keys, TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vAB3:user/release-keys, TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vAB7:user/release-keys, TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vABA:user/release-keys, TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vABM:user/release-keys, TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vABP:user/release-keys, and TCL/A600DL/Delhi_TF:11/RKQ1.201202.002/vABS:user/release-keys); TCL 20XE (TCL/5087Z_BO/Doha_TMO:11/RP1A.200720.011/PB7I-0:user/release-keys and TCL/5087Z_BO/Doha_TMO:11/RP1A.200720.011/PB83-0:user/release-keys); and TCL 10L (TCL/T770B/T1_LITE:10/QKQ1.200329.002/3CJ0:user/release-keys and TCL/T770B/T1_LITE:11/RKQ1.210107.001/8BIC:user/release-keys). This malicious app reads from the "gsm.device.imei0" system property to indirectly obtain the device IMEI.

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

The underlying weakness: Incorrect Privilege Assignment

A product incorrectly assigns a privilege to a particular actor, creating an unintended sphere of control for that actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Run your code using the lowest privileges that are required to accomplish the necessary tasks. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.

More Incorrect Privilege Assignment vulnerabilities (CWE-266)

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

Other vulnerabilities in 30Z_firmware

All 30Z_firmware vulnerabilities

Recent Incorrect Privilege Assignment vulnerabilities

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