Cisco Unified Communications Products Arbitrary File Write Vulnerability

published 2022-04-21 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-26039

cvss: 4.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.4%; EPSS 1.4% chance of exploitation in 30 days, percentile 73%
public exploits: 0; none known

A vulnerability in the software upgrade process of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an authenticated, remote attacker to write arbitrary files on the affected system. This vulnerability is due to improper restrictions applied to a system script. An attacker could exploit this vulnerability by using crafted variables during the execution of a system upgrade. A successful exploit could allow the attacker to overwrite or append arbitrary data to system files using root-level privileges.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-11-06)

Exploit prediction

1.43% chance of exploitation in the next 30 days, higher than 73% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.9	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H
NVD	2.0	8.5	AV:N/AC:L/Au:S/C:N/I:C/A:C

Affected products

Cisco Cisco Unified Communications Manager

Classification

Weakness

CWE-73 External Control of File Name or Path
CWE-610 Externally Controlled Reference to a Resource in Another Sphere

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-arb-write-74QzruUU
vendor-advisory

Sources

CVE List CVE-2022-20789
NVD CVE-2022-20789

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Summary