CVE-2026-20172

CVE-2026-20172 is a medium-severity vulnerability with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-646.

Key facts

Description

A vulnerability in the Lite Agent feature of Cisco Enterprise Chat and Email (ECE) could allow an authenticated, remote attacker to conduct browser-based attacks. To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Agent. This vulnerability is due to inadequate validation of file contents during file upload operations. An attacker could exploit this vulnerability by uploading a file that contains malicious scripts or HTML code, which the application could make available to other users to access. A successful exploit could allow the attacker to execute the contents of that file in the browser of a user and conduct browser-based attacks. 

Frequently asked questions

What is CVE-2026-20172?
A vulnerability in the Lite Agent feature of Cisco Enterprise Chat and Email (ECE) could allow an authenticated, remote attacker to conduct browser-based attacks. To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Agent. This vulnerability is due to inadequate validation of file contents during file upload operations. An attacker could exploit this vulnerability by uploading a file that contains malicious scripts or HTML code, which the application could make available to other users to access. A successful exploit could allow the attacker to execute the contents of that file in the browser of a user and conduct browser-based attacks. 
How severe is CVE-2026-20172?
CVE-2026-20172 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-20172 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-20172?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-20172 have an EU (EUVD) identifier?
Yes. CVE-2026-20172 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27856.
When was CVE-2026-20172 published?
CVE-2026-20172 was published on 2026-05-06 and last updated on 2026-06-17.

References

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