#VU54621 Buffer overflow in Cisco Systems, Inc products - CVE-2021-33478

Vulnerability identifier: #VU54621

Vulnerability risk: Low

CVSSv4.0: 4 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-33478

CWE-ID: CWE-119

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Cisco IP Phone 8800 Series with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8811 with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8841 with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8851 with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8861 with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8845 with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8865 with Multiplatform Firmware
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8845
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8800 Series
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8811
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8841
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8851
Hardware solutions / Office equipment, IP-phones, print servers
Cisco Wireless IP Phone 8821
Hardware solutions / Office equipment, IP-phones, print servers
Cisco IP Phone 8865
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco IP Phone 8861
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a local attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in the TrustZone implementation. An attacker with physical access can dismount the backplate of the device, trigger a specific series of impulses on the chipset and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IP Phone 8800 Series with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8811 with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8841 with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8851 with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8861 with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8845 with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8865 with Multiplatform Firmware: before 11.3.4

Cisco IP Phone 8845: before 14.0.1

Cisco IP Phone 8865: before 14.0.1

Cisco IP Phone 8800 Series: before 14.0.1

Cisco IP Phone 8811: before 14.0.1

Cisco IP Phone 8841: before 14.0.1

Cisco IP Phone 8851: before 14.0.1

Cisco IP Phone 8861: before 14.0.1

Cisco Wireless IP Phone 8821: before 11.0.6 SR1

---

External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-brcm-mxc-jul2021-26LqUZUh

---

Q & A

Can this vulnerability be exploited remotely?

No. The attacker should have physical access to the system in order to successfully exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.