How severe is CVE-2021-24455?

CVE-2021-24455 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-2021-24455 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24455?

CVE-2021-24455 affects Themeum Tutor Lms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24455?

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

When was CVE-2021-24455 published?

CVE-2021-24455 was published on 2021-08-02 and last updated on 2026-06-17.

CVE-2021-24455

CVE-2021-24455 is a medium-severity vulnerability in Themeum Tutor Lms with a CVSS 3.x base score of 5.4. 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 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Themeum Tutor Lms
Published: 2021-08-02
Last modified: 2026-06-17

Description

The Tutor LMS – eLearning and online course solution WordPress plugin before 1.9.2 did not escape the Summary field of Announcements (when outputting it in an attribute), which can be created by users as low as Tutor Instructor. This lead to a Stored Cross-Site Scripting issue, which is triggered when viewing the Announcements list, and could result in privilege escalation when viewed by an admin.

Frequently asked questions

What is CVE-2021-24455?: The Tutor LMS – eLearning and online course solution WordPress plugin before 1.9.2 did not escape the Summary field of Announcements (when outputting it in an attribute), which can be created by users as low as Tutor Instructor. This lead to a Stored Cross-Site Scripting issue, which is triggered when viewing the Announcements list, and could result in privilege escalation when viewed by an admin.
How severe is CVE-2021-24455?: CVE-2021-24455 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-2021-24455 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24455?: CVE-2021-24455 affects Themeum Tutor Lms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24455?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-24455 published?: CVE-2021-24455 was published on 2021-08-02 and last updated on 2026-06-17.

References

https://wpscan.com/vulnerability/9ef14cf1-1e04-4125-a296-9aa5388612f9

Affected products (1)

cpe:2.3:a:themeum:tutor_lms:*:*:*:*:*:wordpress:*:*

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