How severe is CVE-2021-20749?

CVE-2021-20749 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-20749 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20749?

CVE-2021-20749 primarily affects Nendeb Fudousan Plugin. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20749?

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

When was CVE-2021-20749 published?

CVE-2021-20749 was published on 2021-06-28 and last updated on 2026-06-17.

CVE-2021-20749

CVE-2021-20749 is a medium-severity vulnerability in Nendeb Fudousan Plugin with a CVSS 3.x base score of 5.4. 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 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Nendeb Fudousan Plugin
Published: 2021-06-28
Last modified: 2026-06-17

Description

Cross-site scripting vulnerability in Fudousan plugin ver5.7.0 and earlier, Fudousan Plugin Pro Single-User Type ver5.7.0 and earlier, and Fudousan Plugin Pro Multi-User Type ver5.7.0 and earlier allows a remote authenticated attacker to inject an arbitrary script via unspecified vectors.

Frequently asked questions

What is CVE-2021-20749?: Cross-site scripting vulnerability in Fudousan plugin ver5.7.0 and earlier, Fudousan Plugin Pro Single-User Type ver5.7.0 and earlier, and Fudousan Plugin Pro Multi-User Type ver5.7.0 and earlier allows a remote authenticated attacker to inject an arbitrary script via unspecified vectors.
How severe is CVE-2021-20749?: CVE-2021-20749 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-20749 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20749?: CVE-2021-20749 primarily affects Nendeb Fudousan Plugin. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20749?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20749 published?: CVE-2021-20749 was published on 2021-06-28 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:nendeb:fudousan_plugin:*:*:*:*:*:*:*:*
cpe:2.3:a:nendeb:fudousan_plugin_pro_multi-user:*:*:*:*:*:*:*:*
cpe:2.3:a:nendeb:fudousan_plugin_pro_single-user:*:*:*:*:*:*:*:*

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