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

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.

Published: 2025-10-15 Last update: 2025-12-04 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-20350 is rated Low Risk (34.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.04%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-20350

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-21 0.09% 0.04% -0.05%
2 2025-12-05 0.33% 0.09% -0.24%
3 2025-11-21 — 0.33% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-20350

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-20350

Affected software / configurations for CVE-2025-20350

Vendor Product Version Raw CPE
cisco desk_phone_9871_firmware >= 3.0\(1\), <= 3.2\(1\) cpe:2.3:o:cisco:desk_phone_9871_firmware:*:*:*:*:*:*:*:*
cisco desk_phone_9841_firmware >= 3.0\(1\), <= 3.2\(1\) cpe:2.3:o:cisco:desk_phone_9841_firmware:*:*:*:*:*:*:*:*
cisco desk_phone_9851_firmware >= 3.0\(1\), <= 3.2\(1\) cpe:2.3:o:cisco:desk_phone_9851_firmware:*:*:*:*:*:*:*:*
cisco desk_phone_9861_firmware >= 3.0\(1\), <= 3.2\(1\) cpe:2.3:o:cisco:desk_phone_9861_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8865_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8865_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8865_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8865_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8865_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8865_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_7811_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7811_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_7811_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7811_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_7811_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7811_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_7821_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7821_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_7821_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7821_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_7821_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7821_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_7841_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7841_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_7841_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7841_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_7841_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7841_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_7861_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7861_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_7861_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7861_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_7861_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_7861_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8811_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8811_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8811_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8811_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8811_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8811_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8832_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8832_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8832_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8832_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8832_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8832_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8841_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8841_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8841_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8841_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8841_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8841_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8845_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8845_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8845_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8845_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8845_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8845_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8851_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8851_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8851_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8851_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8851_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8851_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8861_firmware < 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8861_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8861_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8861_firmware:14.3\(1\):*:*:*:*:*:*:*
cisco ip_phone_8861_firmware 14.3\(1\) cpe:2.3:o:cisco:ip_phone_8861_firmware:14.3\(1\):sr1:*:*:*:*:*:*
cisco video_phone_8875_firmware < 2.3\(1\) cpe:2.3:o:cisco:video_phone_8875_firmware:*:*:*:*:*:*:*:*
cisco video_phone_8875_firmware >= 3.0\(1\), <= 3.2\(1\) cpe:2.3:o:cisco:video_phone_8875_firmware:*:*:*:*:*:*:*:*
cisco video_phone_8875_firmware 2.3\(1\) cpe:2.3:o:cisco:video_phone_8875_firmware:2.3\(1\):*:*:*:*:*:*:*
cisco video_phone_8875_firmware 2.3\(1\) cpe:2.3:o:cisco:video_phone_8875_firmware:2.3\(1\):sr1:*:*:*:*:*:*
cisco ip_phone_8821_firmware < 11.0\(1\) cpe:2.3:o:cisco:ip_phone_8821_firmware:*:*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(0.7\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(0.7\):mpp:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(1\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(1\):*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(2\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(2\):*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(2\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(2\):sr1:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(2\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(2\):sr2:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):sr1:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):sr2:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):sr3:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):sr4:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):sr5:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(3\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(3\):sr6:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(4\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(4\):*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(4\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(4\):sr1:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(4\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(4\):sr2:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(4\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(4\):sr3:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(5\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(5\):*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(5\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(5\):sr1:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(5\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(5\):sr2:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(5\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(5\):sr3:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(6\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(6\):*:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(6\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(6\):sr1:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(6\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(6\):sr2:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(6\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(6\):sr4:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(6\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(6\):sr5:*:*:*:*:*:*
cisco ip_phone_8821_firmware 11.0\(6\) cpe:2.3:o:cisco:ip_phone_8821_firmware:11.0\(6\):sr6:*:*:*:*:*:*

References for CVE-2025-20350

cvelogic Threat Intelligence