CVE-2026-8203

MediumCVSS 5.4/10Last modified Jul 23, 2026

Description

Concrete CMS 9.5.0 and below has Stored XSS on the height parameter. The controller does not validate or sanitize $height. Any user with editor privileges can inject malicious JavaScript that executes in the context of any visitor's browser, potentially leading to session hijacking, credential theft, or other malicious actions. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 7.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Alfin Joseph for reporting.

Metrics

CVSS 3.1 5.4/10CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
May 21, 2026
Last modified
Jul 23, 2026
NVD status
Analyzed

Related CVEs from 2026

CVE-2026-820357.1PyMuPDF through 1.28.2, fixed in commit b2c8f3a, contains a path traversal vulnerability in the font branch of extract_objects() in src/__maCVE-2026-820398.8UTMStack before 11.2.16 contains a SQL injection vulnerability in UtmAssetGroupService.searchQueryBuilder() that allows authenticated attackCVE-2026-82045.3Concrete CMS 9.5.0 and below is vulnerable to authorization Bypass in the Calendar Event Frontend Dialog which can allow cross-calendar dataCVE-2026-820405.0UTMStack before 11.2.16 contains a server-side request forgery vulnerability in IdentityProviderService.validateMetadataUrl() that allows auCVE-2026-820419.9UTMStack before 11.2.16 contains a missing authorization vulnerability in UTMIncidentCommandWebsocket.processCommand(), the handler mapped tCVE-2026-820429.8UTMStack before 11.2.16 contains an authentication bypass vulnerability that allows remote attackers to gain full administrative API access CVE-2026-820435.3UTMStack before 11.2.16 contains an account enumeration vulnerability that allows unauthenticated attackers to determine registered email adCVE-2026-820447.7UTMStack before 11.2.16 contains a server-side request forgery vulnerability that allows authenticated attackers to make the server request CVE-2026-820456.5UTMStack before 11.2.16 contains a JPQL injection vulnerability that allows authenticated attackers to read arbitrary entity data by exploitCVE-2026-820498.4In CPython 3.13 and earlier, the tarfile module's data and tar extraction filters are vulnerable to crafted archives containing a hard link CVE-2026-82055.3Concrete CMS 9.5.0 and below is vulnerable to authorization bypass in the Calendar Block since action_get_events does not check canView on tCVE-2026-820526.5The $regexFindAll expression can be used by an authenticated user who can run aggregation pipeline stages to crash a MongoDB server (mongod)
CVE-2026-8203: Medium severity, CVSS 5.4 | Vulnix