CVE-2025-20335

A vulnerability in the directory permissions of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 could allow an unauthenticated, remote attacker to write arbitrary files on an affected device. This vulnerability is due to a lack of proper authentication controls. An attacker could exploit this vulnerability by sending a crafted request to an affected device. A successful exploit could allow the attacker to perform arbitrary file writes to specific directories in the underlying operating system. Note: To exploit this vulnerability, Web Access must be enabled on the phone. Web Access is disabled by default.

• cisco desk phone 9841 firmware (>= 3.0\(1\) < 3.3\(1\)) • cisco desk phone 9851 firmware (>= 3.0\(1\) < 3.3\(1\)) • cisco desk phone 9861 firmware (>= 3.0\(1\) < 3.3\(1\)) • cisco desk phone 9871 firmware (>= 3.0\(1\) < 3.3\(1\)) • cisco ip phone 7811 firmware (< 14.3\(1\)) • cisco ip phone 7811 firmware 14.3\(1\) • cisco ip phone 7821 firmware (< 14.3\(1\)) • cisco ip phone 7821 firmware 14.3\(1\) • cisco ip phone 7841 firmware (< 14.3\(1\)) • cisco ip phone 7841 firmware 14.3\(1\) • cisco ip phone 7861 firmware (< 14.3\(1\)) • cisco ip phone 7861 firmware 14.3\(1\) • cisco ip phone 8811 firmware (< 14.3\(1\)) • cisco ip phone 8811 firmware 14.3\(1\) • cisco ip phone 8841 firmware (< 14.3\(1\)) • cisco ip phone 8841 firmware 14.3\(1\) • cisco ip phone 8845 firmware (< 14.3\(1\)) • cisco ip phone 8845 firmware 14.3\(1\) • cisco ip phone 8851 firmware (< 14.3\(1\)) • cisco ip phone 8851 firmware 14.3\(1\) • cisco ip phone 8851nr firmware (< 14.3\(1\)) • cisco ip phone 8851nr firmware 14.3\(1\) • cisco ip phone 8861 firmware (< 14.3\(1\)) • cisco ip phone 8861 firmware 14.3\(1\) • cisco ip phone 8865 firmware (< 14.3\(1\)) • cisco ip phone 8865 firmware 14.3\(1\) • cisco video phone 8875 firmware (< 2.3\(1\)) • cisco video phone 8875 firmware (>= 3.0\(1\) < 3.3\(1\)) • cisco video phone 8875 firmware 2.3\(1\) • cisco ip phone 8821 firmware (< 11.0\(6\)) • cisco ip phone 8821 firmware 11.0\(6\)