Security readout for executives and security teams
Plain-English summary
CVE-2026-30894 is a medium-severity Joomla! CMS cross-site scripting issue in the content history component. It is caused by missing output escaping. Business urgency is highest for organizations running affected Joomla versions where privileged CMS users can access or influence content history workflows.
Executive priority
Prioritize remediation during the next security maintenance window, sooner for public-facing or business-critical Joomla sites. This is not evidenced as actively exploited, but it affects core CMS functionality and privileged administrative workflows.
Technical view
The issue is CWE-79 XSS in Joomla! Core com_contenthistory. Affected ranges are Joomla! CMS 3.0.0 through 5.4.5 and 6.0.0 through 6.1.0. CVSS 4.0 is 6.9 with network attack vector, low complexity, high privileges required, and user interaction present.
Likely exposure
Exposure is likely limited to Joomla! CMS sites in the listed affected ranges, especially administrative environments using content history. The CVSS privileges requirement indicates an attacker needs high-level access before exploitation conditions are met.
Exploitation context
No CISA KEV listing or provided source indicates active exploitation. The vulnerability is still relevant because XSS in CMS administration can affect confidentiality or integrity when privileged users interact with vulnerable views.
Researcher notes
Available public detail is limited to missing output escaping in com_contenthistory. Do not assume exploit availability or broader component impact without vendor confirmation. CVSS indicates high privileges and user interaction are required, with high vulnerable-system confidentiality impact.
Mitigation direction
- Check the Joomla vendor advisory for fixed versions and upgrade guidance.
- Upgrade affected Joomla installations to a release outside the vulnerable ranges.
- Limit high-privilege Joomla administrator access to trusted users only.
- Review whether content history is needed and configured appropriately.
Validation and detection
- Inventory Joomla versions across internet-facing and internal sites.
- Flag Joomla 3.0.0-5.4.5 and 6.0.0-6.1.0 as affected.
- Confirm remediation against the official Joomla security advisory.
- Review administrative access logs for unusual privileged CMS activity.
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-2026-30894 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
- 6.9 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:L/VA:L/SC:N/SI:N/SA: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.
SSVC decision data
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:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N——JoomlaVulnerability scoring details
Base CVSS 4.0 score
6.9MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://developer.joomla.org/security-centre/1035-20260503-core-xss-in-com-contenthistoryCVE reference, Joomla · vendor-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.