SB2023020874 - Multiple vulnerabilities in Discourse

CSH
CYBERSECURITY HELP
Sign In REGISTER

Main Vulnerability Database SB2023020874

SB2023020874 - Multiple vulnerabilities in Discourse

Published: February 8, 2023 Updated: July 1, 2026

Security Bulletin ID SB2023020874
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 5
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 20% Low 80%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 5 vulnerabilities.


1) Incorrect Regular Expression (CVE-ID: CVE-2023-25167)

CWE-ID: CWE-185 - Incorrect Regular Expression

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper validation of git URLs when installing themes. A remote attacker can pass specially crafted input to the application and perform regular expression denial of service (ReDoS) attack.


2) Improper access control (CVE-ID: CVE-2023-23935)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in tag personal message count handling when viewing tags. A remote user can poll a sensitive tag to disclose sensitive information.

User interaction is required to view the tag.


3) Allocation of Resources Without Limits or Throttling (CVE-ID: CVE-2023-28107)

CWE-ID: CWE-770 - Allocation of Resources Without Limits or Throttling

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote user to cause a denial of service.

The vulnerability exists due to allocation of resources without limits or throttling in the backup request functionality when requesting backups multiple times. A remote privileged user can repeatedly request backups to cause a denial of service.

On multisite deployments, exploitation can affect the whole cluster. User interaction is required.


4) Cross-site scripting (CVE-ID: CVE-2023-25172)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear


The vulnerability allows a remote user to execute arbitrary script in a victim's browser.

The vulnerability exists due to cross-site scripting in the full name field when displaying a maliciously crafted URL in a user's name on a post. A remote user can set a crafted full name value to execute arbitrary script in a victim's browser.

Exploitation requires a site with disabled or overly permissive content security policy settings.


5) Improper access control (CVE-ID: CVE-2023-30606)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote user to cause a denial of service.

The vulnerability exists due to improper access control in the SiteSetting class when handling unsanitized dynamic dispatch. A remote privileged user can call arbitrary methods such as clear_cache! or notify_changed! to cause a denial of service.

On multisite deployments, exploitation can affect the entire cluster. User interaction is required.


Remediation

Install update from vendor's website.

References