Security readout for executives and security teams
Plain-English summary
Kentico Xperience sites may allow a logged-in attacker to plant script code inside crafted object names. When an administrator later views related error messages in the admin interface, the script can run in that administrator’s browser. This is a stored XSS issue, not a server takeover by itself.
Executive priority
Treat as a moderate-priority web application issue. It can affect administrator sessions if exploited, but requires prior access and administrator interaction. Remediate during normal vulnerability management cycles, faster for externally exposed or high-value Kentico environments.
Technical view
CVE-2020-36889 is a CWE-79 stored cross-site scripting flaw in Kentico Xperience administration error handling. The advisory scope states Kentico Xperience <= 12.0.90. CVSS 3.1 is 5.4: network reachable, low attack complexity, low privileges required, user interaction required, changed scope, low confidentiality and integrity impact.
Likely exposure
Exposure is most likely for organizations running Kentico Xperience version 12.0.90 or earlier, especially where non-admin authenticated users can create or modify object names that may appear in administrator-visible error messages.
Exploitation context
The source bundle does not indicate known active exploitation, and the CVE is not listed as KEV. Successful exploitation depends on an administrator viewing a malicious stored error message in the administration interface.
Researcher notes
Evidence is limited to the CVE record, Kentico hotfix reference, and VulnCheck advisory. The bundle’s affected field is sparse, while the advisory title scopes <= 12.0.90. Avoid assuming broader product versions or active exploitation without additional vendor confirmation.
Mitigation direction
- Check Kentico’s hotfix page for the applicable Xperience hotfix or upgrade guidance.
- Prioritize remediation on internet-facing or broadly administered Kentico environments.
- Limit administrative interface access to trusted networks and authorized administrators.
- Review roles that can create or rename objects shown in admin error messages.
Validation and detection
- Inventory Kentico Xperience deployments and confirm version and hotfix level.
- Compare installed versions against the advisory scope of <= 12.0.90.
- Confirm administrative interface exposure and access controls.
- Review recent admin error messages for suspicious object names or unexpected script-like content.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-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-2020-36889 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
- 5.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/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:L/UI:R/S:C/C:L/I:L/A:N2.32.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.4MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- Kentico DevNet HotfixesCVE reference · vendor-advisory, patch
- VulnCheck Advisory: Kentico Xperience <= 12.0.90 Administration Interface Stored XSSCVE reference · third-party-advisory
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.
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.