Concrete CMS up to 9.0 RSS Displayer href cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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3.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Concrete CMS up to 9.0. The affected element is an unknown function of the component RSS Displayer. This manipulation of the argument href causes cross site scripting. This vulnerability is registered as CVE-2023-28820. Remote exploitation of the attack is possible. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Concrete CMS up to 9.0 (Content Management System) and classified as problematic. Affected by this vulnerability is some unknown processing of the component RSS Displayer. The manipulation of the argument href with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

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.

The weakness was published 04/28/2023. It is possible to read the advisory at concretecms.org. This vulnerability is known as CVE-2023-28820 since 03/24/2023. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 9.1 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-1289). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.3
VulDB Meta Temp Score: 3.2

VulDB Base Score: 2.4
VulDB Temp Score: 2.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.4
NVD Vector: 🔍

CNA Base Score: 2.0
CNA Vector (MITRE): 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: CMS 9.1

Timelineinfo

03/24/2023 🔍
04/28/2023 +34 days 🔍
04/28/2023 +0 days 🔍
07/12/2025 +806 days 🔍

Sourcesinfo

Advisory: concretecms.org
Status: Confirmed

CVE: CVE-2023-28820 (🔍)
GCVE (CVE): GCVE-0-2023-28820
GCVE (VulDB): GCVE-100-227695
EUVD: 🔍

Entryinfo

Created: 04/28/2023 17:22
Updated: 07/12/2025 21:08
Changes: 04/28/2023 17:22 (53), 05/24/2023 06:25 (11), 07/12/2025 21:08 (16)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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