CVE-2023-4233

What it actually does

A stack-based buffer overflow is triggered in the sms_decode_address_field function during SMS PDU decoding, allowing potential code execution or denial of service from untrusted input.

Why it matters to the business

Systems relying on ofono for telephony on Linux face risk of remote compromise through malicious SMS or rogue base stations, though low EPSS and lack of known exploitation reduce immediate operational urgency; the issue has persisted for over two years without widespread downstream impact noted.

How an attack unfolds

An attacker uses a compromised modem, malicious base station, or crafted SMS to send a malformed PDU that overflows the stack buffer inside sms_decode_address_field during decoding, potentially leading to arbitrary code execution on the host.

How to fix it

Upgrade ofono to the commit 54aa82cbbe3e3bf29dea7eaf35adbc91b94df2ae or later in the GIT repository.

How to confirm the fix worked

Confirm the installed ofono source or binary matches or exceeds commit 54aa82cbbe3e3bf29dea7eaf35adbc91b94df2ae and test SMS PDU handling for crashes or unexpected behavior.

Typical attack path

1. Position malicious base station or compromise modem to deliver crafted SMS
2. Send PDU that reaches sms_decode_address_field during decoding
3. Trigger stack overflow to corrupt memory and gain code execution

How to detect it

Review system and application logs for ofono segmentation faults or abnormal termination during SMS receipt; inspect for unexpected child processes or memory corruption indicators in telephony stacks.

What your security team should do

• Apply the fixed commit 54aa82cbbe3e3bf29dea7eaf35adbc91b94df2ae to all ofono deployments
• Monitor logs for ofono crashes during SMS processing
• Limit exposure by restricting untrusted modem or base station access where feasible