How severe is CVE-2021-24964?

CVE-2021-24964 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-24964 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24964?

CVE-2021-24964 affects Litespeedtech Litespeed Cache. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24964?

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

When was CVE-2021-24964 published?

CVE-2021-24964 was published on 2022-01-03 and last updated on 2026-06-17.

CVE-2021-24964

CVE-2021-24964 is a medium-severity vulnerability in Litespeedtech Litespeed Cache with a CVSS 3.x base score of 6.1. 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 6.1)
CVSS v2: 2.6
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Litespeedtech Litespeed Cache
Published: 2022-01-03
Last modified: 2026-06-17

Description

The LiteSpeed Cache WordPress plugin before 4.4.4 does not properly verify that requests are coming from QUIC.cloud servers, allowing attackers to make requests to certain endpoints by using a specific X-Forwarded-For header value. In addition, one of the endpoint could be used to set CSS code if a setting is enabled, which will then be output in some pages without being sanitised and escaped. Combining those two issues, an unauthenticated attacker could put Cross-Site Scripting payloads in pages visited by users.

Frequently asked questions

What is CVE-2021-24964?: The LiteSpeed Cache WordPress plugin before 4.4.4 does not properly verify that requests are coming from QUIC.cloud servers, allowing attackers to make requests to certain endpoints by using a specific X-Forwarded-For header value. In addition, one of the endpoint could be used to set CSS code if a setting is enabled, which will then be output in some pages without being sanitised and escaped. Combining those two issues, an unauthenticated attacker could put Cross-Site Scripting payloads in pages visited by users.
How severe is CVE-2021-24964?: CVE-2021-24964 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-24964 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24964?: CVE-2021-24964 affects Litespeedtech Litespeed Cache. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24964?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-24964 published?: CVE-2021-24964 was published on 2022-01-03 and last updated on 2026-06-17.

References

https://wpscan.com/vulnerability/e9966b3e-2eb9-4d70-8c18-6a829b4827cc

Affected products (1)

cpe:2.3:a:litespeedtech:litespeed_cache:*:*:*:*:*:wordpress:*:*

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