VulnerabilityPublished 20 Nov 2024Updated 25 Nov 2024

CVE-2024-48985: mbed-os · Classic Buffer Overflow

Affects mbed-osSource CVE Database V5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 20 Nov 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
GitHubmbed-ce/mbed-os`pkg:github/mbed-ce/mbed-os`Other threats	Affected =6.16.0	Fixed in–

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AI-suggested

To mitigate CVE-2024-48985, organizations should prioritize updating MBed OS to a patched version once available from the vendor or community. In the absence of an official patch, developers and integrators should implement input validation to enforce strict limits on HCI packet sizes before processing to prevent oversized packets from triggering allocation failures. Adding robust error handling for memory allocation failures in the HCI packet processing code is critical to prevent buffer overflows. Employing runtime protections such as stack canaries, address space layout randomization (ASLR), and control-flow integrity (CFI) can help reduce exploitation success. Network-level controls should be applied to restrict access to Bluetooth interfaces and limit exposure to untrusted devices. Monitoring for anomalous Bluetooth traffic patterns and implementing intrusion detection systems tailored for embedded environments can provide early warning of exploitation attempts. Finally, conducting thorough code audits and fuzz testing of Bluetooth stack implementations can help identify and remediate similar vulnerabilities proactively.

Description

An issue was discovered in MBed OS 6.16.0. During processing of HCI packets, the software dynamically determines the length of the packet data by reading 2 bytes from the packet data. A buffer is then allocated to contain the entire packet, the size of which is calculated as the length of the packet body determined earlier and the header length. If the allocate fails because the specified packet is too large, no exception handling occurs and hciTrSerialRxIncoming continues to write bytes into the 4-byte large temporary header buffer, leading to a buffer overflow. This can be leveraged into an arbitrary write by an attacker. It is possible to overwrite the pointer to the buffer that is supposed to receive the contents of the packet body but which couldn't be allocated. One can then overwrite the state variable used by the function to determine which step of the parsing process is currently being executed. This advances the function to the next state, where it proceeds to copy data to that arbitrary location. The packet body is then written wherever the corrupted data pointer is pointing.

Impact

The impact of CVE-2024-48985 is primarily on the integrity of affected systems, as it allows an attacker to perform arbitrary memory writes remotely without authentication or user interaction. This can lead to unauthorized code execution, corruption of critical system data, or disruption of Bluetooth communication processes. Devices running MBed OS 6.16.0 that handle HCI packets are at risk, including a wide range of IoT devices such as sensors, wearables, industrial controllers, and other embedded systems that rely on Bluetooth connectivity. Successful exploitation could enable attackers to gain persistent control over devices, pivot within networks, or disrupt critical operations. Given the prevalence of MBed OS in embedded and IoT markets, the vulnerability poses a global risk, especially to industries relying on Bluetooth-enabled embedded devices for operational technology, healthcare, smart home, and industrial automation. The lack of exception handling on allocation failure indicates a design flaw that could be exploited at scale if weaponized. Although no known exploits are reported yet, the ease of exploitation and network accessibility make this a high-risk vulnerability that could be leveraged in targeted or widespread attacks.

Summary

CVE-2024-48985 is a buffer overflow vulnerability identified in MBed OS version 6.16.0, specifically within the handling of Host Controller Interface (HCI) packets used in Bluetooth communication. The vulnerability stems from the dynamic determination of packet length by reading two bytes from the packet data, followed by an attempt to allocate a buffer sized to hold the entire packet (header plus body). If the allocation fails because the packet is too large, the function hciTrSerialRxIncoming does not handle this failure properly and continues to write incoming bytes into a fixed-size 4-byte temporary header buffer. This unchecked write leads to a buffer overflow condition. Exploiting this overflow, an attacker can overwrite the pointer intended to reference the allocated packet body buffer (which was not allocated due to failure) and also corrupt a state variable controlling the parsing process. By manipulating these pointers and state, the attacker can cause the function to copy packet data to arbitrary memory locations, effectively enabling arbitrary memory writes. This can lead to code execution or corruption of critical data structures. The vulnerability does not require any privileges or user interaction and can be exploited remotely over the network, making it a severe threat to devices running the affected MBed OS version. The vulnerability is classified under CWE-120 (Classic Buffer Overflow) and has a CVSS v3.1 base score of 7.5, indicating high severity with network attack vector, low attack complexity, no privileges required, no user interaction, unchanged scope, no confidentiality impact, high integrity impact, and no availability impact. No patches or known exploits are currently reported, but the risk remains significant given the nature of the flaw and the widespread use of MBed OS in IoT and embedded devices.

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #11
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
OWASP Cheat Sheets
Docker Security (opens in a new tab)
XML Security (opens in a new tab)
OWASP ASVS 4.0.3
V5.4.1 (opens in a new tab)
V14.1.2 (opens in a new tab)
V13.3.1 (opens in a new tab)
Attack patterns
Buffer Overflow via Environment Variables (opens in a new tab)
Overflow Buffers (opens in a new tab)
Client-side Injection-induced Buffer Overflow (opens in a new tab)
Filter Failure through Buffer Overflow (opens in a new tab)
MIME Conversion (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Feb 2026, 21:50 UTC

WeaknessesCWE-120

Technical details

References

Community reviews

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