TI-2026-16470 Aliases CVE-2026-20281 GHSA-998p-wvfv-584p

Memory leak in Cisco Session Initiation Protocol Software

MEDIUM 40CWE-401Published 2026-09-02 · Updated 2026-09-02

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-401.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00571 47th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Cisco	Cisco Session Initiation Protocol (SIP) Software	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; 11.7(1); 12.1(1); 11.0(0.7) MPP; 9.3(4) 3rd Party; 12.5(1)SR2; 10.2(1)SR1; 9.3(4)SR3 3rd Party; 10.2(1); 12.5(1); 10.3(1)SR2; 11-0-1MSR1-1; 10.4(1) 3rd Party; 12.5(1)SR1; 11.5(1)SR1; 10.1(1)SR2; 12.0(1)SR2; 12.6(1); 10.3(1.11) 3rd Party; 12.0(1); 12.0(1)SR1; 9.3(3); 12.5(1)SR3; 10.3(1)SR4b; 9.3(4)SR1 3rd Party; 10.3(1)SR5; 10.1(1.9); 10.3(1.9) 3rd Party; 9.3(4)SR2 3rd Party; 10.3(1)SR1; 10.3(1)SR3; 10.1(1)SR1; 12.0(1)SR3; 12.6(1)SR1; 12.7(1); 10.3(1)SR6; 12.8(1); 12.7(1)SR1; 11.0(2)SR1; 11.0(4); 11.0(2); 11.0(4)SR3; 11.0(5); 11.0(3)SR2; 11.0(3)SR4; 11.0(3)SR3; 11.0(2)SR2; 11.0(4)SR1; 11.0(5)SR3; 11.0(3); 11.0(5)SR2; 11.0(3)SR6; 11.0(5)SR1; 11.0(4)SR2; 11.0(3)SR1; 11.0(3)SR5; 11.0(6); 12.8(1)SR1; 12.8(1)SR2; 14.0(1); 14.0(1)SR1; 11.0(6)SR1; 10.3(1)SR7; 14.0(1)SR2; 14.1(1); 14.0(1)SR3; 11.0(6)SR2; 14.1(1)SR1; 14.1(1)SR2; 11.0(6)SR4; 14.2(1); 14.2(1)SR1; 11.0(6)SR5; 14.1(1)SR3; 14.2(1)SR2; 3.1(1); 3.0(1); 2.3(1); 2.3(1)SR1; 2.2(1); 2.1(1); 2.0(1); 14.2(1)SR3; 3.1(1)SR1; 14.3(1); 3.2(1); 14.3(1)SR1; 14.2(1)SR4; 3.3(1); 11.0(6)SR6; 14.3(1)SR2; 3.4(1); 14.3(1)SR3; 3.5(1); 11.0(6)SR7; 3.5(1)SR1; 14.4(1); 3.6(1); 4.0(1); 14.4(1)SR1; 4.1(1); 14.4(1)SR2; 4.1(1)SR1	—	No fix listed	CNA

Cisco Session Initiation Protocol (SIP) Software VendorCisco Affected 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; 11.7(1); 12.1(1); 11.0(0.7) MPP; 9.3(4) 3rd Party; 12.5(1)SR2; 10.2(1)SR1; 9.3(4)SR3 3rd Party; 10.2(1); 12.5(1); 10.3(1)SR2; 11-0-1MSR1-1; 10.4(1) 3rd Party; 12.5(1)SR1; 11.5(1)SR1; 10.1(1)SR2; 12.0(1)SR2; 12.6(1); 10.3(1.11) 3rd Party; 12.0(1); 12.0(1)SR1; 9.3(3); 12.5(1)SR3; 10.3(1)SR4b; 9.3(4)SR1 3rd Party; 10.3(1)SR5; 10.1(1.9); 10.3(1.9) 3rd Party; 9.3(4)SR2 3rd Party; 10.3(1)SR1; 10.3(1)SR3; 10.1(1)SR1; 12.0(1)SR3; 12.6(1)SR1; 12.7(1); 10.3(1)SR6; 12.8(1); 12.7(1)SR1; 11.0(2)SR1; 11.0(4); 11.0(2); 11.0(4)SR3; 11.0(5); 11.0(3)SR2; 11.0(3)SR4; 11.0(3)SR3; 11.0(2)SR2; 11.0(4)SR1; 11.0(5)SR3; 11.0(3); 11.0(5)SR2; 11.0(3)SR6; 11.0(5)SR1; 11.0(4)SR2; 11.0(3)SR1; 11.0(3)SR5; 11.0(6); 12.8(1)SR1; 12.8(1)SR2; 14.0(1); 14.0(1)SR1; 11.0(6)SR1; 10.3(1)SR7; 14.0(1)SR2; 14.1(1); 14.0(1)SR3; 11.0(6)SR2; 14.1(1)SR1; 14.1(1)SR2; 11.0(6)SR4; 14.2(1); 14.2(1)SR1; 11.0(6)SR5; 14.1(1)SR3; 14.2(1)SR2; 3.1(1); 3.0(1); 2.3(1); 2.3(1)SR1; 2.2(1); 2.1(1); 2.0(1); 14.2(1)SR3; 3.1(1)SR1; 14.3(1); 3.2(1); 14.3(1)SR1; 14.2(1)SR4; 3.3(1); 11.0(6)SR6; 14.3(1)SR2; 3.4(1); 14.3(1)SR3; 3.5(1); 11.0(6)SR7; 3.5(1)SR1; 14.4(1); 3.6(1); 4.0(1); 14.4(1)SR1; 4.1(1); 14.4(1)SR2; 4.1(1)SR1 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-20281
2026-10-03 Alias added: GHSA-998p-wvfv-584p
2026-10-25 Priority changed: LOW → MEDIUM

References

Other 1

cisco-sa-phone-dos-txMYNRzv

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TI-2026-16344 Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0

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Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences