How severe is CVE-2026-26989?

CVE-2026-26989 has a CVSS 3.x base score of 4.3, 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 low.

Is CVE-2026-26989 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-26989?

CVE-2026-26989 affects Librenms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-26989?

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

Does CVE-2026-26989 have an EU (EUVD) identifier?

Yes. CVE-2026-26989 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8038.

When was CVE-2026-26989 published?

CVE-2026-26989 was published on 2026-02-20 and last updated on 2026-06-17.

CVE-2026-26989

CVE-2026-26989 is a medium-severity vulnerability in Librenms 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-8038
Weakness: CWE-79
Affected product: Librenms
Published: 2026-02-20
Last modified: 2026-06-17

Description

LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. An attacker with administrative privileges can inject malicious scripts that execute in the browser context of any user who accesses the Alert Rules page. This issue has been fixed in version 26.2.0.

Frequently asked questions

What is CVE-2026-26989?: LibreNMS is an auto-discovering PHP/MySQL/SNMP based network monitoring tool. Versions 25.12.0 and below are affected by a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Rules workflow. An attacker with administrative privileges can inject malicious scripts that execute in the browser context of any user who accesses the Alert Rules page. This issue has been fixed in version 26.2.0.
How severe is CVE-2026-26989?: CVE-2026-26989 has a CVSS 3.x base score of 4.3, 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 low.
Is CVE-2026-26989 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-26989?: CVE-2026-26989 affects Librenms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-26989?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-26989 have an EU (EUVD) identifier?: Yes. CVE-2026-26989 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8038.
When was CVE-2026-26989 published?: CVE-2026-26989 was published on 2026-02-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:librenms:librenms:*:*:*:*:*:*:*:*

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