How severe is CVE-2021-33512?

CVE-2021-33512 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-2021-33512 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33512?

CVE-2021-33512 affects Plone. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33512?

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

When was CVE-2021-33512 published?

CVE-2021-33512 was published on 2021-05-21 and last updated on 2026-06-17.

CVE-2021-33512

CVE-2021-33512 is a medium-severity vulnerability in Plone 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% (48th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Plone
Published: 2021-05-21
Last modified: 2026-06-17

Description

Plone through 5.2.4 allows stored XSS attacks (by a Contributor) by uploading an SVG or HTML document.

Frequently asked questions

What is CVE-2021-33512?: Plone through 5.2.4 allows stored XSS attacks (by a Contributor) by uploading an SVG or HTML document.
How severe is CVE-2021-33512?: CVE-2021-33512 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-2021-33512 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (48th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33512?: CVE-2021-33512 affects Plone. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33512?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33512 published?: CVE-2021-33512 was published on 2021-05-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:plone:plone:*:*:*:*:*:*:*:*

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