Cisco IP Phone 8821 Firmware vulnerabilities

14 CVEs affecting Cisco IP Phone 8821 Firmware, 1 known to be exploited (CISA KEV), with EPSS scores. Latest: CVE-2025-20351, published 2025-10-15.

Highest priority

Known exploited (CISA KEV) first, then by EPSS exploit probability.

CVE-2020-3161: Cisco IP Phones Web Server Remote Code Execution and Denial-of-Service Vulnerability, published 2020-04-15. Critical severity, CVSS 9.8. Actively exploited: in CISA KEV since 2021-11-03. EPSS: 83.9% chance of exploitation in the next 30 days. A vulnerability in the web server for Cisco IP Phones could allow an unauthenticated, remote attacker to execute code with root privileges or cause a reload of an affected IP phone, resulting in a…
CVE-2020-26139, published 2021-05-11. Medium severity, CVSS 5.3. EPSS: 6.5% chance of exploitation in the next 30 days. An issue was discovered in the kernel in NetBSD 7.1. An Access Point (AP) forwards EAPOL frames to other clients even though the sender has not yet successfully authenticated to the AP. This might be…
CVE-2020-24588, published 2021-05-11. Low severity, CVSS 3.5. EPSS: 3.6% chance of exploitation in the next 30 days. The 802.11 standard that underpins Wi-Fi Protected Access (WPA, WPA2, and WPA3) and Wired Equivalent Privacy (WEP) doesn't require that the A-MSDU flag in the plaintext QoS header field is…
CVE-2019-1716, published 2019-03-22. Critical severity, CVSS 9.8. EPSS: 3.1% chance of exploitation in the next 30 days. A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 7800 Series and Cisco IP Phone 8800 Series could allow an unauthenticated,…
CVE-2020-26140, published 2021-05-11. Medium severity, CVSS 6.5. EPSS: 2.9% chance of exploitation in the next 30 days. An issue was discovered in the ALFA Windows 10 driver 6.1316.1209 for AWUS036H. The WEP, WPA, WPA2, and WPA3 implementations accept plaintext frames in a protected Wi-Fi network. An adversary can…
CVE-2020-24587, published 2021-05-11. Low severity, CVSS 2.6. EPSS: 2.6% chance of exploitation in the next 30 days. The 802.11 standard that underpins Wi-Fi Protected Access (WPA, WPA2, and WPA3) and Wired Equivalent Privacy (WEP) doesn't require that all fragments of a frame are encrypted under the same key. An…
CVE-2019-1763, published 2019-03-22. High severity, CVSS 7.5. EPSS: 1.9% chance of exploitation in the next 30 days. A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 8800 Series could allow an unauthenticated, remote attacker to bypass…
CVE-2019-1765, published 2019-03-22. Medium severity, CVSS 6.5. EPSS: 1.4% chance of exploitation in the next 30 days. A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 8800 Series could allow an authenticated, remote attacker to write arbitrary…
CVE-2019-1764, published 2019-03-22. High severity, CVSS 8.8. EPSS: 0.7% chance of exploitation in the next 30 days. A vulnerability in the web-based management interface of Session Initiation Protocol (SIP) Software for Cisco IP Phone 8800 Series could allow an unauthenticated, remote attacker to conduct a…
CVE-2023-20018, published 2023-01-20. Medium severity, CVSS 6.5. EPSS: 0.6% chance of exploitation in the next 30 days. A vulnerability in the web-based management interface of Cisco IP Phone 7800 and 8800 Series Phones could allow an unauthenticated, remote attacker to bypass authentication on an affected device. …

Latest

CVE-2025-20351, published 2025-10-15. Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 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…
CVE-2025-20350, published 2025-10-15. High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 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…
CVE-2025-20336, published 2025-09-03. High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days. 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 access…
CVE-2025-20335, published 2025-09-03. Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days. 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…