How severe is CVE-2021-25929?

CVE-2021-25929 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-25929 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25929?

CVE-2021-25929 primarily affects Opennms Horizon. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-25929?

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

When was CVE-2021-25929 published?

CVE-2021-25929 was published on 2021-05-20 and last updated on 2026-06-17.

CVE-2021-25929

CVE-2021-25929 is a medium-severity vulnerability in Opennms Horizon with a CVSS 3.x base score of 4.8. 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 4.8)
CVSS v2: 3.5
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Opennms Horizon
Published: 2021-05-20
Last modified: 2026-06-17

Description

In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1; meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.6-1 are vulnerable to Stored Cross-Site Scripting since there is no validation on the input being sent to the `name` parameter in `noticeWizard` endpoint. Due to this flaw an authenticated attacker could inject arbitrary script and trick other admin users into downloading malicious files.

Frequently asked questions

What is CVE-2021-25929?: In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1; meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.6-1 are vulnerable to Stored Cross-Site Scripting since there is no validation on the input being sent to the `name` parameter in `noticeWizard` endpoint. Due to this flaw an authenticated attacker could inject arbitrary script and trick other admin users into downloading malicious files.
How severe is CVE-2021-25929?: CVE-2021-25929 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-25929 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25929?: CVE-2021-25929 primarily affects Opennms Horizon. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-25929?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-25929 published?: CVE-2021-25929 was published on 2021-05-20 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:opennms:horizon:*:*:*:*:*:*:*:*
cpe:2.3:a:opennms:meridian:*:*:*:*:*:*:*:*

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CVE-2021-25931 — High (CVSS 8.8): In OpenNMS Horizon, versions opennms-1-0-stable through opennms-27.1.0-1; OpenNMS Meridian, versions…
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