How severe is CVE-2021-24378?

CVE-2021-24378 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-2021-24378 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24378?

CVE-2021-24378 affects Autoptimize. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24378?

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

When was CVE-2021-24378 published?

CVE-2021-24378 was published on 2021-06-21 and last updated on 2026-06-17.

CVE-2021-24378

CVE-2021-24378 is a medium-severity vulnerability in Autoptimize 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% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Autoptimize
Published: 2021-06-21
Last modified: 2026-06-17

Description

The Autoptimize WordPress plugin before 2.7.8 does not check for malicious files such as .html in the archive uploaded via the 'Import Settings' feature. As a result, it is possible for a high privilege user to upload a malicious file containing JavaScript code inside an archive which will execute when a victim visits index.html inside the plugin directory.

Frequently asked questions

What is CVE-2021-24378?: The Autoptimize WordPress plugin before 2.7.8 does not check for malicious files such as .html in the archive uploaded via the 'Import Settings' feature. As a result, it is possible for a high privilege user to upload a malicious file containing JavaScript code inside an archive which will execute when a victim visits index.html inside the plugin directory.
How severe is CVE-2021-24378?: CVE-2021-24378 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-2021-24378 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24378?: CVE-2021-24378 affects Autoptimize. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24378?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-24378 published?: CVE-2021-24378 was published on 2021-06-21 and last updated on 2026-06-17.

References

https://wpscan.com/vulnerability/375bd694-1a30-41af-bbd4-8a8ee54f0dbf

Affected products (1)

cpe:2.3:a:autoptimize:autoptimize:*:*:*:*:*:wordpress:*:*

More vulnerabilities in Autoptimize

CVE-2021-24376 — Critical (CVSS 9.8): The Autoptimize WordPress plugin before 2.7.8 attempts to delete malicious files (such as .php) form the uploaded…
CVE-2021-24377 — High (CVSS 8.1): The Autoptimize WordPress plugin before 2.7.8 attempts to remove potential malicious files from the extracted archive…
CVE-2020-24948 — High (CVSS 7.2): The ao_ccss_import AJAX call in Autoptimize Wordpress Plugin 2.7.6 does not ensure that the file provided is a…
CVE-2023-2113 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 3.1.7 does not sanitise and escape the settings imported from a previous…
CVE-2022-2635 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 3.1.1 does not sanitise and escape some of its settings, which could allow high…
CVE-2021-24332 — Medium (CVSS 4.8): The Autoptimize WordPress plugin before 2.8.4 was missing proper escaping and sanitisation in some of its settings,…

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