CVE-2026-20281
published 2026-09-02CVE-2026-20281: A vulnerability in Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 that are running Cisco Session Initiation…
PriorityP346high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.33%
26.1th percentile
A vulnerability in Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 that are running Cisco Session Initiation Protocol (SIP) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
This vulnerability is due to improper memory management when an affected device processes HTTP packets. An attacker could exploit this vulnerability by sending a continuous stream of crafted HTTP packets to the device. A successful exploit could allow the attacker to cause the affected device to continuously consume memory, resulting in a DoS condition. A manual reboot of the device is required to recover from this condition.
Note: For this vulnerability to be exploitable, the phone must be registered to Cisco Unified Communications Manager (Unified CM) and have Web Access enabled. Web Access is disabled by default.
Affected
110 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
| cisco | cisco_session_initiation_protocol_software | — | — |
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GHSA
A vulnerability in Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 that are running Cisco Session Initiation Protocol (SIP) Software could allow an unauth
ghsa_unreviewed·2026-09-02
CVE-2026-20281 [HIGH] CWE-401 A vulnerability in Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 that are running Cisco Session Initiation Protocol (SIP) Software could allow an unauth
A vulnerability in Cisco Desk Phone 9800 Series, Cisco IP Phone 7800 and 8800 Series, and Cisco Video Phone 8875 that are running Cisco Session Initiation Protocol (SIP) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
This vulnerability is due to improper memory management when an affected device processes HTTP packets. An attacker could exploit this vulnerability by sending a continuous stream of crafted HTTP packets to the device. A successful exploit could allow the attacker to cause the affected device to continuously consume memory, resulting in a DoS condition. A manual reboot of the device is required to recover from this condition.
Note: For this vulnerability to be exploitable, the phone must be register
VulDB
Cisco Session Initiation Protocol Software up to 14.4(1)SR2 denial of service (EUVD-2026-70209)
vuldb·2026-09-02·CVSS 7.5
CVE-2026-20281 [HIGH] Cisco Session Initiation Protocol Software up to 14.4(1)SR2 denial of service (EUVD-2026-70209)
A vulnerability labeled as critical has been found in Cisco Session Initiation Protocol Software. The impacted element is an unknown function. Such manipulation leads to denial of service.
This vulnerability is referenced as CVE-2026-20281. It is possible to launch the attack remotely. No exploit is available.
The affected component should be upgraded.
No detection rules found.
No public exploits indexed.
2026-09-02
Published