Analyst readout for executives and security teams
Plain-English summary
CVE-2021-36855 affects the Booking Ultra Pro WordPress plugin through version 1.1.4. A malicious site could abuse a logged-in user’s browser interaction to inject script into the WordPress context. Business impact is usually moderate: account/session exposure or content manipulation risk, not direct server takeover based on the provided CVSS data.
Executive priority
Treat as a moderate-priority web application risk. Prioritize sites that are public-facing, business-critical, or administered by privileged users. It is not listed as known exploited in the provided sources.
Technical view
The issue combines CSRF and XSS in Booking Ultra Pro <= 1.1.4. CVSS 3.1 is 6.1 with network attack vector, low complexity, no privileges required, user interaction required, changed scope, and low confidentiality/integrity impact. The provided sources do not identify a fixed version, affected endpoint, proof of exploitation, or detailed remediation.
Likely exposure
Exposure is limited to WordPress sites running Booking Ultra Pro version 1.1.4 or earlier. Internet-facing WordPress sites with authenticated administrators or staff using the affected plugin are the main concern.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation. Exploitation requires user interaction and likely depends on inducing a logged-in user to trigger a crafted request or page flow.
Researcher notes
Evidence is sparse. The CVE record and supplied advisory identify CSRF-enabled XSS, but do not provide affected parameters, exploit primitives, or a fixed release in the bundle. Avoid assuming exploitability beyond the CVSS vector and stated affected version range.
Mitigation direction
- Inventory WordPress sites for Booking Ultra Pro installations and versions.
- Check the WordPress plugin page and Patchstack advisory for fixed-version guidance.
- Upgrade only according to official vendor or trusted security advisory instructions.
- If no safe update exists, consider disabling the plugin after business review.
- Limit WordPress administrator browsing exposure while remediation is pending.
Validation and detection
- Confirm whether Booking Ultra Pro is installed on each WordPress site.
- Record the plugin version and flag versions 1.1.4 or earlier.
- Review security monitoring for suspicious script injection or unexpected plugin setting changes.
- Verify remediation by confirming the plugin is updated, disabled, or removed.
- Document any exception where the plugin must remain active.
Public sources used
Based on public source material and reviewed before publication.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-352: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-36855 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://wordpress.org/plugins/booking-ultra-pro/CVE reference · x_refsource_CONFIRM
- https://patchstack.com/database/vulnerability/booking-ultra-pro/wordpress-booking-ultra-pro-plugin-1-1-4-cross-site-scripting-xss-via-cross-site-request-forgery-csrf-vulnerability?_s_id=cveCVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Cross-Site Request Forgery (CSRF)
Cross-Site Request Forgery (CSRF) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.