How severe is CVE-2021-24253?

CVE-2021-24253 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-24253 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24253?

CVE-2021-24253 affects Classyfrieds Project Classyfrieds. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24253?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-24253 published?

CVE-2021-24253 was published on 2021-05-06 and last updated on 2026-06-17.

CVE-2021-24253

CVE-2021-24253 is a high-severity vulnerability in Classyfrieds Project Classyfrieds with a CVSS 3.x base score of 8.8. 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-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Classyfrieds Project Classyfrieds
Published: 2021-05-06
Last modified: 2026-06-17

Description

The Classyfrieds WordPress plugin through 3.8 does not properly check the uploaded file when an authenticated user adds a listing, only checking the content-type in the request. This allows any authenticated user to upload arbitrary PHP files via the Add Listing feature of the plugin, leading to RCE.

Frequently asked questions

What is CVE-2021-24253?: The Classyfrieds WordPress plugin through 3.8 does not properly check the uploaded file when an authenticated user adds a listing, only checking the content-type in the request. This allows any authenticated user to upload arbitrary PHP files via the Add Listing feature of the plugin, leading to RCE.
How severe is CVE-2021-24253?: CVE-2021-24253 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-24253 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24253?: CVE-2021-24253 affects Classyfrieds Project Classyfrieds. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24253?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-24253 published?: CVE-2021-24253 was published on 2021-05-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:classyfrieds_project:classyfrieds:*:*:*:*:*:wordpress:*:*

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