PatchSiren cyber security CVE debrief
CVE-2026-39620 priyanshumittal CVE debrief
A critical Cross-Site Request Forgery (CSRF) vulnerability exists in the Appointment theme, potentially allowing attackers to upload a web shell to a web server. The issue affects Appointment theme versions from n/a through <= 3.5.5. This vulnerability has been assigned a CVSS score of 9.6, indicating a high severity level. The vulnerability could allow an attacker to trick authenticated users into performing unintended actions on the web application, potentially leading to the upload of a web shell. Users should prioritize updating to a patched version to prevent potential exploitation.
- Vendor
- priyanshumittal
- Product
- Appointment
- CVSS
- CRITICAL 9.6
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-04-08
- Original CVE updated
- 2026-07-24
- Advisory published
- 2026-04-08
- Advisory updated
- 2026-07-24
Who should care
Users of Appointment theme versions up to 3.5.5 should prioritize updating to a patched version to prevent potential exploitation. This includes administrators and security teams responsible for maintaining and securing websites that use the Appointment theme. Additionally, operators and platform administrators should review the vulnerability details to assess potential impact and implement necessary mitigations.
Technical summary
The CVE-2026-39620 vulnerability is a Cross-Site Request Forgery (CSRF) issue in the Appointment theme. This vulnerability could allow an attacker to trick authenticated users into performing unintended actions on the web application, potentially leading to the upload of a web shell. The vulnerability has a CVSS score of 9.6, indicating critical severity. The CVSS vector is CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Defenders should implement CSRF protection mechanisms and monitor for suspicious requests.
Defensive priority
High
Recommended defensive actions
- Update Appointment theme to a version beyond 3.5.5
- Implement CSRF protection mechanisms
- Monitor for suspicious requests
- Restrict file uploads
- Regularly review and update plugins and themes
Evidence notes
The CVE record was published on 2026-04-08T09:16:32.110Z and last modified on 2026-07-24T21:10:00.143Z. The NVD entry is currently Deferred. Evidence is limited to public sources and may not reflect the full scope or impact of the vulnerability. Defenders should verify affected deployments and review official advisories for specific guidance.
Sources and references
Verified primary and authoritative sources
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CVE-2026-39620 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-39620
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-39620 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-39620
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.