How severe is CVE-2021-35479?

CVE-2021-35479 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-35479 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35479?

CVE-2021-35479 affects Nagios Log Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-35479?

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

When was CVE-2021-35479 published?

CVE-2021-35479 was published on 2021-07-30 and last updated on 2026-06-17.

CVE-2021-35479

CVE-2021-35479 is a medium-severity vulnerability in Nagios Log Server with a CVSS 3.x base score of 5.4. Its EPSS exploit-prediction score of 13% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 13% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Nagios Log Server
Published: 2021-07-30
Last modified: 2026-06-17

Description

Nagios Log Server before 2.1.9 contains Stored XSS in the custom column view for the alert history and audit log function through the affected pp parameter. This affects users who open a crafted link or third-party web page.

Frequently asked questions

What is CVE-2021-35479?: Nagios Log Server before 2.1.9 contains Stored XSS in the custom column view for the alert history and audit log function through the affected pp parameter. This affects users who open a crafted link or third-party web page.
How severe is CVE-2021-35479?: CVE-2021-35479 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-35479 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 13% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35479?: CVE-2021-35479 affects Nagios Log Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-35479?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-35479 published?: CVE-2021-35479 was published on 2021-07-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nagios:log_server:*:*:*:*:*:*:*:*

More vulnerabilities in Nagios Log Server

CVE-2025-44823 — Critical (CVSS 9.9): Nagios Log Server before 2024R1.3.2 allows authenticated users to retrieve cleartext administrative API keys via a…
CVE-2025-34277 — Critical (CVSS 9.8): Nagios Log Server versions prior to 2024R1.3.1 contain a code injection vulnerability where malformed dashboard ID…
CVE-2025-34274 — Critical (CVSS 9.8): Nagios Log Server versions prior to 2024R2.0.3 contain an execution with unnecessary privileges vulnerability as it…
CVE-2025-34271 — Critical (CVSS 9.8): Nagios Log Server versions prior to 2024R2.0.2 contain a vulnerability in the cluster manager component when…
CVE-2025-34298 — High (CVSS 8.8): Nagios Log Server versions prior to 2024R1.3.2 contain a privilege escalation vulnerability in the account email-change…
CVE-2025-44824 — High (CVSS 8.5): Nagios Log Server before 2024R1.3.2 allows authenticated users (with read-only API access) to stop the Elasticsearch…

All CVEs affecting Nagios Log Server →

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →