How severe is CVE-2021-4340?

CVE-2021-4340 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-4340 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4340?

CVE-2021-4340 affects Stylemixthemes Ulisting. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4340?

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

When was CVE-2021-4340 published?

CVE-2021-4340 was published on 2023-06-07 and last updated on 2026-06-17.

CVE-2021-4340

CVE-2021-4340 is a critical-severity vulnerability in Stylemixthemes Ulisting with a CVSS 3.x base score of 9.8. 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-89.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-89
Affected product: Stylemixthemes Ulisting
Published: 2023-06-07
Last modified: 2026-06-17

Description

The uListing plugin for WordPress is vulnerable to generic SQL Injection via the ‘listing_id’ parameter in versions up to, and including, 1.6.6 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.

Frequently asked questions

What is CVE-2021-4340?: The uListing plugin for WordPress is vulnerable to generic SQL Injection via the ‘listing_id’ parameter in versions up to, and including, 1.6.6 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.
How severe is CVE-2021-4340?: CVE-2021-4340 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-4340 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4340?: CVE-2021-4340 affects Stylemixthemes Ulisting. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4340?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-4340 published?: CVE-2021-4340 was published on 2023-06-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:stylemixthemes:ulisting:*:*:*:*:*:wordpress:*:*

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