CVE-2021-32735: Cross-site scripting (XSS) from field and configuration text displayed in the Panel
Noroxi assessment
Priority: Monitor (action score 21/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.53% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. A user must open a link or visit a page. No special conditions are required; it is repeatable.
- Fixed version: getkirby/cms (Packagist) 3.5.7.
Low priority for now. Upgrade to getkirby/cms (Packagist) 3.5.7 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
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.
- Published
- Jul 2, 2021
- Updated
- Jun 16, 2026
- EPSS
- 0.5% · 45th percentile
- CWE
- CWE-80
Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 21 / 40 · 5.4 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CNA vs NVD score
- NVD
- 5.4
- CNA · GitHub_M
- 7.1
- 1.7 point gap
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| getkirby | kirby | cpe:2.3:a:getkirby:kirby |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- getkirby kirbybefore 3.5.7
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
getkirby kirby
- <= 3.5.5, <= 3.5.6affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Packagist | getkirby/cms | before 3.5.7 | 3.5.7 |
Same product
getkirby: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-38490Kirby XML External Entity (XXE) vulnerability in the XML data handler41Plan
- CVE-2026-44177Kirby: Pre-authentication path traversal and PHP file inclusion during user lookup36Monitor
- CVE-2026-54003Kirby: External Initialization of the Panel on reverse proxy setups with the `Forwarded` header36Monitor
Published before and after this one in the same product
- ← EarlierCVE-2020-26255Dec 8, 2020 · PHP Phar archives could be uploaded and executed in Kirby36Monitor
- ← EarlierCVE-2021-29460Apr 27, 2021 · Cross-site scripting (XSS) from unsanitized uploaded SVG files22Monitor
- Later →CVE-2021-41252Nov 16, 2021 · Cross-site scripting (XSS) from writer field content in the site frontend21Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Packagist:getkirby/cms | 3.5.7 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- low · data or configuration can be modified
- Availability
- none
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality impact
- Low
- Integrity impact
- Low
- Availability impact
- None
Weakness class (CWE)
CWE-80 · Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Change log
- Fix✗ → ✓
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References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.