How severe is CVE-2021-44223?

CVE-2021-44223 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-44223 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44223?

CVE-2021-44223 affects Wordpress. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-44223?

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-2021-44223 published?

CVE-2021-44223 was published on 2021-11-25 and last updated on 2026-06-17.

CVE-2021-44223

CVE-2021-44223 is a high-severity vulnerability in Wordpress with a CVSS 3.x base score of 8.1. Its EPSS exploit-prediction score of 29% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 7.5
EPSS exploit prediction: 29% (98th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Wordpress
Published: 2021-11-25
Last modified: 2026-06-17

Description

WordPress before 5.8 lacks support for the Update URI plugin header. This makes it easier for remote attackers to execute arbitrary code via a supply-chain attack against WordPress installations that use any plugin for which the slug satisfies the naming constraints of the WordPress.org Plugin Directory but is not yet present in that directory.

Frequently asked questions

What is CVE-2021-44223?: WordPress before 5.8 lacks support for the Update URI plugin header. This makes it easier for remote attackers to execute arbitrary code via a supply-chain attack against WordPress installations that use any plugin for which the slug satisfies the naming constraints of the WordPress.org Plugin Directory but is not yet present in that directory.
How severe is CVE-2021-44223?: CVE-2021-44223 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-44223 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 29% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44223?: CVE-2021-44223 affects Wordpress. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-44223?: 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-2021-44223 published?: CVE-2021-44223 was published on 2021-11-25 and last updated on 2026-06-17.

References

Affected products (1)

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

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Threat intelligence

Threat-intel indicators referencing this CVE:

64.202.190.35 (ipv4-addr)