Ce mail provient de l'extérieur, restons vigilants ===================================================================== CERT-Renater Note d'Information No. 2026/VULN852 _____________________________________________________________________ DATE : 19/08/2026 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running Joomla! CMS versions prior to 5.4.8, 6.1.3. ===================================================================== https://developer.joomla.org/security-centre/1070-20260803-core-inconsistent-acl-checks-for-mutating-webservice-endpoints.html https://developer.joomla.org/security-centre/1068-20260801-core-response-header-injection-in-download-views.html https://developer.joomla.org/security-centre/1071-20260804-core-improper-acl-checks-for-custom-fields-webservice-endpoints.html https://developer.joomla.org/security-centre/1072-20260805-core-improper-acl-checks-for-category-webservice-endpoints.html https://developer.joomla.org/security-centre/1073-20260806-core-xss-through-schema-org-outputs.html https://developer.joomla.org/security-centre/1074-20260807-core-mfa-authentication-bypass.html https://developer.joomla.org/security-centre/1075-20260808-core-improper-acl-checks-for-batch-copy-actions.html https://developer.joomla.org/security-centre/1076-20260809-core-improper-acl-checks-when-injection-schema-org-contact-data.html https://developer.joomla.org/security-centre/1077-20260810-core-unrestricted-uploads-of-shtml-files.html _____________________________________________________________________ Security Announcements [20260803] - Core - Inconsistent ACL checks for mutating webservice endpoints Project: Joomla! SubProject: CMS Impact: High Severity: Moderate Probability: Low Versions: 4.0.0-5.4.7, 6.0.0-6.1.2 Exploit type: Incorrect Access Control Reported Date: 2026-07-15 Fixed Date: 2026-08-18 CVE Number: CVE-2026-71574 Description An improper access check allows unauthorized users to perform mutation actions in webservice endpoints, where the same mutation was restricted in the backend UI. Affected Installs Joomla! CMS versions 4.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: Paul, Sorrachat, tms _____________________________________________________________________ [20260801] - Core - Response header injection in download views Project: Joomla! SubProject: CMS Impact: Low Severity: Low Probability: Low Versions: 3.0.0-5.4.7, 6.0.0-6.1.2 Exploit type: Response header injection Reported Date: 2026-07-02 Fixed Date: 2026-08-18 CVE Number: CVE-2026-71572 Description Lack of output processing allowed a header injection in the multiple download views, leading to reflected file download / content-type confusion. Affected Installs Joomla! CMS versions 3.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: arib06 _____________________________________________________________________ [20260804] - Core - Improper ACL checks for custom fields webservice endpoints Project: Joomla! SubProject: CMS Impact: Moderate Severity: Moderate Probability: Low Versions: 4.0.0-5.4.7, 6.0.0-6.1.2 Exploit type: Incorrect Access Control Reported Date: 2026-07-06 Fixed Date: 2026-08-18 CVE Number: CVE-2026-72531 Description An improper access check allows unauthorized users to create fields for inaccessible components. Affected Installs Joomla! CMS versions 4.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: ebadfd _____________________________________________________________________ [20260805] - Core - Improper ACL checks for category webservice endpoints Project: Joomla! SubProject: CMS Impact: Moderate Severity: Moderate Probability: Low Versions: 4.0.0-5.4.7, 6.0.0-6.1.2 Exploit type: Incorrect Access Control Reported Date: 2026-07-15 Fixed Date: 2026-08-18 CVE Number: CVE-2026-72532 Description An improper access check allows unauthorized users to create categories for inaccessible components. Affected Installs Joomla! CMS versions 4.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: Amin İsayev, Geo (GitHub.com/geo-chen) _____________________________________________________________________ [20260806] - Core - XSS through schema.org outputs Project: Joomla! SubProject: CMS Impact: Moderate Severity: Moderate Probability: Low Versions: 5.1.0-5.4.7, 6.0.0-6.1.2 Exploit type: XSS Reported Date: 2026-07-21 Fixed Date: 2026-08-18 CVE Number: CVE-2026-73336 Description Improper escaping flags lead to an XSS vector in schema.org markup outputs. Affected Installs Joomla! CMS versions 5.1.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: Amin İsayev, Geo (GitHub.com/geo-chen) _____________________________________________________________________ [20260807] - Core - MFA Authentication Bypass Project: Joomla! SubProject: CMS Impact: High Severity: Moderate Probability: Moderate Versions: 4.0.0-5.4.7,6.0.0-6.1.2 Exploit type: Authentication Bypass Reported Date: 2026-07-25 Fixed Date: 2026-08-18 CVE Number: CVE-2026-73337 Description Insufficient state checks lead to a vector that allows to bypass 2FA checks. Affected Installs Joomla! CMS versions 4.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: bloman, Matej Rada _____________________________________________________________________ [20260808] - Core - Improper ACL checks for batch copy actions Project: Joomla! SubProject: CMS Impact: Low Severity: Low Probability: Low Versions: 4.0.0-5.4.7,6.0.0-6.1.2 Exploit type: Incorrect Access Control Reported Date: 2026-07-28 Fixed Date: 2026-08-18 CVE Number: CVE-2026-73371 Description An improper access check allows unauthorized users to perform copy batch operations on uneditable items. Affected Installs Joomla! CMS versions 4.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: Sabuhi Mammadov _____________________________________________________________________ [20260809] - Core - Improper ACL checks when injection schema.org contact data Project: Joomla! SubProject: CMS Impact: Low Severity: Low Probability: Low Versions: 5.1.0-5.4.7,6.0.0-6.1.2 Exploit type: Incorrect Access Control Reported Date: 2026-07-31 Fixed Date: 2026-08-18 CVE Number: CVE-2026-73372 Description An improper access check injects contact information for unaccessible contact items into schema.org snippets. Affected Installs Joomla! CMS versions 5.1.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: Stefan Wendhausen _____________________________________________________________________ [20260810] - Core - Unrestricted uploads of SHTML files Project: Joomla! SubProject: CMS Impact: High Severity: Low Probability: Low Versions: 1.0.0-5.4.7,6.0.0-6.1.2 Exploit type: Unrestricted Upload of File with Dangerous Type Reported Date: 2026-07-29 Fixed Date: 2026-08-18 CVE Number: CVE-2026-73373 Description The default list of dangerous files did not include SHTML files. On servers that executed these files, that could lead to code execution. Affected Installs Joomla! CMS versions 1.0.0-5.4.7, 6.0.0-6.1.2 Solution Upgrade to version 5.4.8, 6.1.3 Contact The JSST at the Joomla! Security Centre. Reported By: Valentin Lobstein (Chocapikk) ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 23/25 Rue Daviel | fax : 01-53-94-20-41 + + 75013 Paris | email:cert@support.renater.fr + =========================================================