Calendar < 1.3.18 - Contributor+ Stored XSS via event_link Parameter
Priority HIGH 65CWE-79Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-79.
Summary
The Calendar WordPress plugin before 1.3.18 does not properly escape a user-supplied event field before outputting it inside an HTML attribute on a public-facing page, allowing users with the Contributor role to inject arbitrary JavaScript that executes in the browser of anyone viewing the calendar.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00431 37th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Fixed Calendar (Unknown): 1.3.18
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Unknown | Calendar | before 1.3.18 | 1.3.18 | Patch available | CNA |
- Calendar VendorUnknown Affected before 1.3.18 Fixed in 1.3.18 Patch available CNA
Remediation
- Fix · CNA Calendar (Unknown) Fixed in 1.3.18
Timeline
- 2026-10-02 Threatist record created from CVE-2026-14827
- 2026-10-03 Alias added: GHSA-x423-2wcq-r3qx
References
Sources
- CVE-2026-14827 · CVE Program
- CVE-2026-14827 · NVD
- FIRST EPSS
- GHSA-x423-2wcq-r3qx · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences