How severe is CVE-2021-32735?

CVE-2021-32735 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2021-32735 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32735?

CVE-2021-32735 affects Getkirby Kirby. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32735?

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-2021-32735 published?

CVE-2021-32735 was published on 2021-07-02 and last updated on 2026-06-17.

CVE-2021-32735

CVE-2021-32735 is a high-severity vulnerability in Getkirby Kirby with a CVSS 3.x base score of 7.1. 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: High (CVSS 3.x base score 7.1)
CVSS v2: 3.5
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Getkirby Kirby
Published: 2021-07-02
Last modified: 2026-06-17

Description

Kirby is a content management system. In Kirby CMS versions 3.5.5 and 3.5.6, the Panel's `ListItem` component (used in the pages and files section for example) displayed HTML in page titles as it is. This could be used for cross-site scripting (XSS) attacks. Malicious authenticated Panel users can escalate their privileges if they get access to the Panel session of an admin user. Visitors without Panel access can use the attack vector if the site allows changing site data from a frontend form. Kirby 3.5.7 patches the vulnerability. As a partial workaround, site administrators can protect against attacks from visitors without Panel access by validating or sanitizing provided data from the frontend form.

Frequently asked questions

What is CVE-2021-32735?: Kirby is a content management system. In Kirby CMS versions 3.5.5 and 3.5.6, the Panel's `ListItem` component (used in the pages and files section for example) displayed HTML in page titles as it is. This could be used for cross-site scripting (XSS) attacks. Malicious authenticated Panel users can escalate their privileges if they get access to the Panel session of an admin user. Visitors without Panel access can use the attack vector if the site allows changing site data from a frontend form. Kirby 3.5.7 patches the vulnerability. As a partial workaround, site administrators can protect against attacks from visitors without Panel access by validating or sanitizing provided data from the frontend form.
How severe is CVE-2021-32735?: CVE-2021-32735 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2021-32735 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32735?: CVE-2021-32735 affects Getkirby Kirby. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32735?: 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-2021-32735 published?: CVE-2021-32735 was published on 2021-07-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:getkirby:kirby:*:*:*:*:*:*:*:*

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