Cisco Duo Authentication Proxy Information Disclosure Vulnerability

published 2025-08-20 last yr. modified 2026-06-17 4mo ago also EUVD-2025-25387

cvss: 4.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits: 0; none known

A vulnerability in the debug logging function of Cisco Duo Authentication Proxy could allow an authenticated, high-privileged, remote attacker to view sensitive information in a system log file.

This vulnerability is due to insufficient masking of sensitive information before it is written to system log files. An attacker could exploit this vulnerability by accessing logs on an affected system. A successful exploit could allow the attacker to view sensitive information that should be restricted. 

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: last yr. (2025-08-20)

Exploit prediction

0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).

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:H/I:N/A:N

Affected products

Cisco Cisco Duo Authentication Proxy

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

Sources

CVE List CVE-2025-20345
NVD CVE-2025-20345

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