CVE intelligence and bounded remediation

CVE-2021-33478 — Cisco Ip Phone 8800 Firmware security vulnerability

Medium CVSS 6.8

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.

Severity
Medium
CVSS
6.8 (3.1)
Published
2021-07-22
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-119

Affected products

  • cisco / ip_phone_8800_firmware
  • cisco / ip_phone_8800_series_with_multiplatform_firmware
  • cisco / ip_phone_8811_firmware
  • cisco / ip_phone_8811_with_multiplatform_firmware
  • cisco / ip_phone_8841_firmware
  • cisco / ip_phone_8841_with_multiplatform_firmware

Showing 6 representative product identities from 15 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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