CVE-2023-28820
Stored cross site scripting in RSS displayer
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- High
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
- Record
CVE-2023-28820- CVSS 3.1
- 2.0 Low
CVSS:3.1/AC:H/AV:N/A:N/C:L/I:N/PR:H/S:U/UI:R - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2023-1289
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
- Record
EUVD-2023-1289- CVSS 3.1
- 2.0 Low
CVSS:3.1/AC:H/AV:N/A:N/C:L/I:N/PR:H/S:U/UI:R - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-fgxj-g7x3-85cq
Stored cross site scripting in RSS displayer
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
- Record
GHSA-fgxj-g7x3-85cq- CVSS 3.1
- 2.0 Low
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
- Record
CVE-2023-28820- CVSS 3.1
- 2.0 Low
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:N/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
- Record
CVE-2023-28820- CVSS 3.1
- 2.0 Low
CVSS:3.1/AC:H/AV:N/A:N/C:L/I:N/PR:H/S:U/UI:R - Updated
- 2026-11-02
OSVGHSA-fgxj-g7x3-85cq
Stored cross site scripting in RSS displayer
Concrete CMS (previously concrete5) before 9.1 is vulnerable to stored XSS in RSS Displayer via the href attribute because the link element input was not sanitized.
- Record
GHSA-fgxj-g7x3-85cq- CVSS 3.1
- 2.0 Low
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
concrete5/concrete5Packagist |
before 9.1.0 | 9.1.0 |
concrete5/concrete5Packagist |
before 9.1.0, plus listed versions 8.08.0.18.0.28.0.38.1.0 Show 45 moreShow less8.2.08.2.0RC28.2.18.3.08.3.18.3.28.4.08.4.0RC38.4.0RC48.4.18.4.28.4.38.4.48.4.58.5.08.5.0RC18.5.0RC28.5.18.5.108.5.118.5.128.5.138.5.148.5.158.5.168.5.178.5.188.5.198.5.28.5.208.5.218.5.38.5.48.5.58.5.68.5.6RC18.5.78.5.88.5.99.0.09.0.0RC19.0.0RC39.0.0RC49.0.19.0.2 |
9.1.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-28820 is a low vulnerability (CVSS 2.0) in Concretecms Concrete Cms, published April 28, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 33rd percentile. Fixed in concrete5/concrete5 9.1.0.
References
github.com/concretecms/concretecms/releases
concretecms.org/about/project-news/security/concrete-cms-security-advisory-2023-04-20
nvd.nist.gov/vuln/detail/CVE-2023-28820