How severe is CVE-2021-26024?

CVE-2021-26024 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-26024 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 19% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26024?

CVE-2021-26024 affects Nagios Favorites. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26024?

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

When was CVE-2021-26024 published?

CVE-2021-26024 was published on 2021-02-03 and last updated on 2026-06-17.

CVE-2021-26024

CVE-2021-26024 is a medium-severity vulnerability in Nagios Favorites with a CVSS 3.x base score of 5.3. Its EPSS exploit-prediction score of 19% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-639.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 19% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-639
Affected product: Nagios Favorites
Published: 2021-02-03
Last modified: 2026-06-17

Description

The Favorites component before 1.0.2 for Nagios XI 5.8.0 is vulnerable to Insecure Direct Object Reference: it is possible to create favorites for any other user account.

Frequently asked questions

What is CVE-2021-26024?: The Favorites component before 1.0.2 for Nagios XI 5.8.0 is vulnerable to Insecure Direct Object Reference: it is possible to create favorites for any other user account.
How severe is CVE-2021-26024?: CVE-2021-26024 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-26024 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 19% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26024?: CVE-2021-26024 affects Nagios Favorites. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26024?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26024 published?: CVE-2021-26024 was published on 2021-02-03 and last updated on 2026-06-17.

References

https://www.nagios.com/products/security/

Affected products (1)

cpe:2.3:a:nagios:favorites:*:*:*:*:*:*:*:*

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CVE-2021-26023 — Medium (CVSS 6.1): The Favorites component before 1.0.2 for Nagios XI 5.8.0 is vulnerable to XSS.

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