CVE-2025-20350

HIGH

Cisco SIP Software - Buffer Overflow

Title source: llm
STIX 2.1

Description

A vulnerability in the web UI of Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 running Cisco SIP Software could allow an unauthenticated, remote attacker to cause a DoS condition on an affected device. This vulnerability is due to a buffer overflow when an affected device processes HTTP packets. An attacker could exploit this vulnerability by sending crafted HTTP input to the device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Note: To exploit this vulnerability, the phone must be registered to Cisco Unified Communications Manager and have Web Access enabled. Web Access is disabled by default.

Scores

CVSS v3 7.5
EPSS 0.0004
EPSS Percentile 12.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-121
Status published
Products (25)
cisco/desk_phone_9841_firmware 3.0\(1\) - 3.2\(1\)
cisco/desk_phone_9851_firmware 3.0\(1\) - 3.2\(1\)
cisco/desk_phone_9861_firmware 3.0\(1\) - 3.2\(1\)
cisco/desk_phone_9871_firmware 3.0\(1\) - 3.2\(1\)
cisco/ip_phone_7811_firmware 14.3\(1\) (2 CPE variants)
cisco/ip_phone_7811_firmware < 14.3\(1\)
cisco/ip_phone_7821_firmware 14.3\(1\) (2 CPE variants)
cisco/ip_phone_7821_firmware < 14.3\(1\)
cisco/ip_phone_7841_firmware 14.3\(1\) (2 CPE variants)
cisco/ip_phone_7841_firmware < 14.3\(1\)
... and 15 more
Published Oct 15, 2025
Tracked Since Feb 18, 2026