High 7.5Published Oct 15, 2025

CVE-2025-20350Cisco Desk Phone 9800 Series, IP Phone 7800 and 8800 Series, and Video Phone 8875 with SIP Firmware Denial of Service Vulnerability

Updated under an hour ago (Oct 28, 2026, 2:30 AM ET)

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It affects Cisco Session Initiation Protocol (SIP) Software and 17 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Cisco Session Initiation Protocol (SIP) Software

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-121
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: cisco
NVD analysis: Analyzed
Record last updated: Oct 15, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Cisco Cisco Session Initiation Protocol (SIP) Software cisco:session_initiation_protocol_sip_software (from the name)	12.1(1)SR1; 11.5(1); 10.3(2); 10.2(2); 10.3(1); 10.3(1)SR4; 11.0(1); 10.4(1)SR2 3rd Party; and 88 more ranges	CNA record
cisco desk_phone_9871_firmware cisco:desk_phone_9871_firmware	from 3.0\(1\) through 3.2\(1\)	NVD
cisco desk_phone_9841_firmware cisco:desk_phone_9841_firmware	from 3.0\(1\) through 3.2\(1\)	NVD
cisco desk_phone_9851_firmware cisco:desk_phone_9851_firmware	from 3.0\(1\) through 3.2\(1\)	NVD
cisco desk_phone_9861_firmware cisco:desk_phone_9861_firmware	from 3.0\(1\) through 3.2\(1\)	NVD
cisco ip_phone_8865_firmware cisco:ip_phone_8865_firmware	before 14.3\(1\); 14.3(1); 14.3(1)	NVD
cisco ip_phone_7811_firmware cisco:ip_phone_7811_firmware	before 14.3\(1\); 14.3(1); 14.3(1)	NVD
cisco ip_phone_7821_firmware cisco:ip_phone_7821_firmware	before 14.3\(1\); 14.3(1); 14.3(1)	NVD
cisco ip_phone_7841_firmware cisco:ip_phone_7841_firmware	before 14.3\(1\); 14.3(1); 14.3(1)	NVD
cisco ip_phone_7861_firmware cisco:ip_phone_7861_firmware	before 14.3\(1\); 14.3(1); 14.3(1)	NVD
1–10 of 18

References

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-phone-dos-FPyjLV7A	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.