CVE-2021-33478
CVE-2021-33478 is a medium-severity vulnerability in Cisco Ip Phone 8800 Firmware with a CVSS 3.x base score of 6.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.
Key facts
- Severity: Medium (CVSS 3.x base score 6.8)
- CVSS v2: 4.6
- EPSS exploit prediction: 0% (23rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Cisco Ip Phone 8800 Firmware
- Published:
- Last modified:
Description
The TrustZone implementation in certain Broadcom MediaxChange firmware could allow an unauthenticated, physically proximate attacker to achieve arbitrary code execution in the TrustZone Trusted Execution Environment (TEE) of an affected device. This, for example, affects certain Cisco IP Phone and Wireless IP Phone products before 2021-07-07. Exploitation is possible only when the attacker can disassemble the device in order to control the voltage/current for chip pins.
Frequently asked questions
- What is CVE-2021-33478?
- The TrustZone implementation in certain Broadcom MediaxChange firmware could allow an unauthenticated, physically proximate attacker to achieve arbitrary code execution in the TrustZone Trusted Execution Environment (TEE) of an affected device. This, for example, affects certain Cisco IP Phone and Wireless IP Phone products before 2021-07-07. Exploitation is possible only when the attacker can disassemble the device in order to control the voltage/current for chip pins.
- How severe is CVE-2021-33478?
- CVE-2021-33478 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-33478 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-33478?
- CVE-2021-33478 primarily affects Cisco Ip Phone 8800 Firmware. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-33478?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-33478 published?
- CVE-2021-33478 was published on 2021-07-22 and last updated on 2026-06-17.
References
Affected products (15)
- cpe:2.3:o:cisco:ip_phone_8800_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8800_series_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8811_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8811_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8841_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8841_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8845_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8845_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8851_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8851_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8861_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8861_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8865_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ip_phone_8865_with_multiplatform_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:wireless_ip_phone_8821_firmware:*:*:*:*:*:*:*:*
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