Security readout for executives and security teams
Plain-English summary
This issue affects Adobe Experience Manager Inbox calendar fields. An authenticated Author user could save malicious script that later runs in another user’s browser when they view the affected page. For organizations using vulnerable AEM versions, this can threaten account actions, sensitive content, and business workflows exposed through AEM.
Executive priority
Prioritize remediation where AEM supports public sites, customer portals, regulated content, or distributed authoring. The weakness needs authenticated Author access, but successful abuse can affect other users’ browser sessions and sensitive AEM workflows.
Technical view
CVE-2020-9742 is a CWE-79 cross-site scripting flaw in Adobe Experience Manager. The CVE description identifies stored XSS requiring Author privileges and user interaction by a victim. Affected versions are AEM 6.5.5.0 and below, 6.4.8.1 and below, and 6.3.3.8 and below. CVSS 3.1 is 9.0 with changed scope and high CIA impact.
Likely exposure
Exposure is most likely where Adobe Experience Manager deployments run the affected 6.5, 6.4, or 6.3 maintenance levels and allow Author users to access the Inbox calendar feature. Public authoring environments, shared author accounts, or broad author privileges increase business risk.
Exploitation context
The bundle does not show CISA KEV listing or other evidence of active exploitation. Exploitation requires a user with Author privileges to store malicious script and a victim to open a page containing the vulnerable field. Treat this as high-impact authenticated XSS, not unauthenticated remote compromise.
Researcher notes
The provided title says reflected XSS, while the CVE description says stored XSS. The analysis follows the description because it gives the affected privilege and execution flow. No exploit code, exploit-in-the-wild evidence, or specific fixed build numbers were included in the bundle.
Mitigation direction
- Check Adobe APSB20-56 for the vendor-supported update path.
- Upgrade affected AEM instances according to Adobe guidance.
- Restrict Author privileges to users with a business need.
- Review shared or stale Author accounts and remove unnecessary access.
- Prioritize remediation for internet-reachable or partner-accessible author environments.
Validation and detection
- Inventory AEM versions across author and publish environments.
- Confirm whether versions are 6.5.5.0 or below, 6.4.8.1 or below, or 6.3.3.8 or below.
- Identify users and groups with Author privileges.
- Check whether the Inbox calendar feature is enabled or used.
- Verify remediation against Adobe APSB20-56 after updates are applied.
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-2020-9742 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
- Critical
- CVSS
- 9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
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:H/I:H/A:H2.36Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9CriticalVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://helpx.adobe.com/security/products/experience-manager/apsb20-56.htmlCVE reference · x_refsource_MISC
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.