CVE-2019-9503Public exploit

Code execution via unchecked firmware-event subtype

Published Jan 16, 2020 · Updated Aug 4, 2024

Frame validation bypass in Broadcom brcmfmac before commit a4176ec356c73a46c07c181c6d04039fafa34a9f allows remote attackers to execute code. The USB and PCIe receive paths enable event handling, while brcmf_fweh_process_skb omits the subtype check that distinguishes host events from wireless frames. An unauthenticated attacker within WiFi range can inject a subtype that passes the firmware filter and reaches kernel event handlers, typically causing a crash and, in the worst case, code execution.

CVSS severity8.3
High
EPSS probability3.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Frame validation bypass in Broadcom brcmfmac before commit a4176ec356c73a46c07c181c6d04039fafa34a9f allows remote attackers to execute code. The USB and PCIe receive paths enable event handling, while brcmf_fweh_process_skb omits the subtype check that distinguishes host events from wireless frames. An unauthenticated attacker within WiFi range can inject a subtype that passes the firmware filter and reaches kernel event handlers, typically causing a crash and, in the worst case, code execution.

The record

CVE
CVE-2019-9503
Published
Jan 16, 2020
Updated
Aug 4, 2024
Vendor
Broadcom
Product
brcmfmac
Classifications
CWE-20, T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 16, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=commit prior to a4176ec356c73a46c07c181c6d04039fafa34a9f

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Broadcom · brcmfmacversion=commit prior to a4176ec356c73a46c07c181c6d04039fafa34a9f

Published CVSS scores

6.8CERT/CCAV:A/AC:H/Au:N/C:C/I:C/A:C
8.3NIST NVDCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
5.3CERT/CCAV:A/AC:H/Au:N/C:C/I:C/A:C/E:POC/RL:OF/RC:ND
7.9NIST NVDAV:A/AC:M/Au:N/C:C/I:C/A:C
7.9CERT/CCCVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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