CyberSecBulletin
CVE-2022-26941NVD status: Modified

Mobile Radio: Use of Externally-Controlled Format String

CVE-2022-26941 is a high-severity use of externally-controlled format string vulnerability in Mobile Radio from Motorola, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected Mobile Radio versions: MTM5000; mtm5000. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.37% 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 Mobile Radio you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
MotorolaMobile RadioMTM5000; mtm5000Not stated
MotorolaMtm5500 FirmwareNot specified in the recordNot stated
MotorolaMtm5400 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
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
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:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.6CriticalCNA (ncsc.nl)
CVSS 3.18.8HighNVD

Official description

A format string vulnerability exists in Motorola MTM5000 series firmware AT command handler for the AT+CTGL command. An attacker-controllable string is improperly handled, allowing for a write-anything-anywhere scenario. This can be leveraged to obtain arbitrary code execution inside the teds_app binary, which runs with root privileges.

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

The underlying weakness: Use of Externally-Controlled Format String

The product uses a function that accepts a format string as an argument, but the format string originates from an external source.

How developers prevent this class of flaw

  • Choose a language that is not subject to this flaw.
  • Ensure that all format string functions are passed a static string which cannot be controlled by the user, and that the proper number of arguments are always sent to that function as well. If at all possible, use functions that do not support the %n operator in format strings.
  • Run compilers and linkers with high warning levels, since they may detect incorrect usage.

More Use of Externally-Controlled Format String vulnerabilities (CWE-134)

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 references

Other vulnerabilities in Mobile Radio

All Mobile Radio vulnerabilities

Recent Use of Externally-Controlled Format String vulnerabilities

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