How severe is CVE-2019-25375?

CVE-2019-25375 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2019-25375 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-25375?

CVE-2019-25375 affects Opnsense. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-25375?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2019-25375 have an EU (EUVD) identifier?

Yes. CVE-2019-25375 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2019-19420.

When was CVE-2019-25375 published?

CVE-2019-25375 was published on 2026-02-15 and last updated on 2026-06-17.

CVE-2019-25375

CVE-2019-25375 is a medium-severity vulnerability in Opnsense with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v4: 5.1
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2019-19420
Weakness: CWE-79
Affected product: Opnsense
Published: 2026-02-15
Last modified: 2026-06-17

Description

OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by submitting crafted input to the mailserver parameter. Attackers can send POST requests to the monit interface with JavaScript payloads in the mailserver parameter to execute arbitrary code in users' browsers.

Frequently asked questions

What is CVE-2019-25375?: OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by submitting crafted input to the mailserver parameter. Attackers can send POST requests to the monit interface with JavaScript payloads in the mailserver parameter to execute arbitrary code in users' browsers.
How severe is CVE-2019-25375?: CVE-2019-25375 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2019-25375 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-25375?: CVE-2019-25375 affects Opnsense. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-25375?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2019-25375 have an EU (EUVD) identifier?: Yes. CVE-2019-25375 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2019-19420.
When was CVE-2019-25375 published?: CVE-2019-25375 was published on 2026-02-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:opnsense:opnsense:19.1:*:*:*:*:*:*:*

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