Cisco Unity Connection up to 15SU3 HTTPS path traversal

Summaryinfo

A vulnerability was found in Cisco Unity Connection. It has been rated as problematic. The impacted element is an unknown function of the component HTTPS Handler. The manipulation leads to path traversal. This vulnerability is traded as CVE-2026-20078. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Cisco Unity Connection. It has been rated as problematic. This issue affects an unknown function of the component HTTPS Handler. The manipulation with an unknown input leads to a path traversal vulnerability. Using CWE to declare the problem leads to CWE-23. The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory. Impacted is confidentiality. The summary by CVE is:

Multiple vulnerabilities in Cisco Unity Connection could allow an authenticated, remote attacker to download arbitrary files from an affected system. To exploit these vulnerabilities, the attacker must have valid administrative credentials.  These vulnerabilities are due to improper sanitization of user input to the web-based management interface. An attacker could exploit these vulnerabilities by sending a crafted HTTPS request. A successful exploit could allow the attacker to download arbitrary files from an affected system.

The advisory is shared at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2026-20078 since 10/08/2025. The exploitation is known to be easy. The attack may be initiated remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/16/2026). MITRE ATT&CK project uses the attack technique T1006 for this issue.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at EUVD (EUVD-2026-22956) and CERT Bund (WID-SEC-2026-1149). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Cisco Unity Connection

Productinfo

Type

• Unified Communication Software

Vendor

• Cisco

Name

• Unity Connection

Version

• 12.5(1)
• 12.5(1)SU1
• 12.5(1)SU2
• 12.5(1)SU3
• 12.5(1)SU4
• 12.5(1)SU5
• 12.5(1)SU6
• 12.5(1)SU7
• 12.5(1)SU8
• 12.5(1)SU8a
• 12.5(1)SU9
• 14
• 14SU1
• 14SU2
• 14SU3
• 14SU3a
• 14SU4
• 14SU5
• 15
• 15SU1
• 15SU2
• 15SU3

License

• commercial

Website

• Vendor: https://www.cisco.com/

CPE 2.3info

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CPE 2.2info

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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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