3.5
LOW
CVE-2023-22489
"Flarum Discussion Hijacking Vulnerability"
Description

Flarum is a discussion platform for websites. If the first post of a discussion is permanently deleted but the discussion stays visible, any actor who can view the discussion is able to create a new reply via the REST API, no matter the reply permission or lock status. This includes users that don't have a validated email. Guests cannot successfully create a reply because the API will fail with a 500 error when the user ID 0 is inserted into the database. This happens because when the first post of a discussion is permanently deleted, the `first_post_id` attribute of the discussion becomes `null` which causes access control to be skipped for all new replies. Flarum automatically makes discussions with zero comments invisible so an additional condition for this vulnerability is that the discussion must have at least one approved reply so that `discussions.comment_count` is still above zero after the post deletion. This can open the discussion to uncontrolled spam or just unintentional replies if users still had their tab open before the vulnerable discussion was locked and then post a reply when they shouldn't be able to. In combination with the email notification settings, this could also be used as a way to send unsolicited emails. Versions between `v1.3.0` and `v1.6.3` are impacted. The vulnerability has been fixed and published as flarum/core v1.6.3. All communities running Flarum should upgrade as soon as possible. There are no known workarounds.

INFO

Published Date :

Jan. 13, 2023, 7:15 p.m.

Last Modified :

Nov. 7, 2023, 4:07 a.m.

Remotely Exploitable :

Yes !

Impact Score :

1.4

Exploitability Score :

2.1
Affected Products

The following products are affected by CVE-2023-22489 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Flarum flarum
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2023-22489.

URL Resource
https://github.com/flarum/framework/commit/12f14112a0ecd1484d97330b82beb2a145919015 Patch Third Party Advisory
https://github.com/flarum/framework/releases/tag/v1.6.3 Release Notes Third Party Advisory
https://github.com/flarum/framework/security/advisories/GHSA-hph3-hv3c-7725 Mitigation Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2023-22489 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2023-22489 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Changed Description Flarum is a discussion platform for websites. If the first post of a discussion is permanently deleted but the discussion stays visible, any actor who can view the discussion is able to create a new reply via the REST API, no matter the reply permission or lock status. This includes users that don't have a validated email. Guests cannot successfully create a reply because the API will fail with a 500 error when the user ID 0 is inserted into the database. This happens because when the first post of a discussion is permanently deleted, the `first_post_id` attribute of the discussion becomes `null` which causes access control to be skipped for all new replies. Flarum automatically makes discussions with zero comments invisible so an additional condition for this vulnerability is that the discussion must have at least one approved reply so that `discussions.comment_count` is still above zero after the post deletion. This can open the discussion to uncontrolled spam or just unintentional replies if users still had their tab open before the vulnerable discussion was locked and then post a reply when they shouldn't be able to. In combination with the email notification settings, this could also be used as a way to send unsolicited emails. Versions between `v1.3.0` and `v1.6.3` are impacted. The vulnerability has been fixed and published as flarum/core v1.6.3. All communities running Flarum should upgrade as soon as possible. There are no known workarounds. Flarum is a discussion platform for websites. If the first post of a discussion is permanently deleted but the discussion stays visible, any actor who can view the discussion is able to create a new reply via the REST API, no matter the reply permission or lock status. This includes users that don't have a validated email. Guests cannot successfully create a reply because the API will fail with a 500 error when the user ID 0 is inserted into the database. This happens because when the first post of a discussion is permanently deleted, the `first_post_id` attribute of the discussion becomes `null` which causes access control to be skipped for all new replies. Flarum automatically makes discussions with zero comments invisible so an additional condition for this vulnerability is that the discussion must have at least one approved reply so that `discussions.comment_count` is still above zero after the post deletion. This can open the discussion to uncontrolled spam or just unintentional replies if users still had their tab open before the vulnerable discussion was locked and then post a reply when they shouldn't be able to. In combination with the email notification settings, this could also be used as a way to send unsolicited emails. Versions between `v1.3.0` and `v1.6.3` are impacted. The vulnerability has been fixed and published as flarum/core v1.6.3. All communities running Flarum should upgrade as soon as possible. There are no known workarounds.
  • Initial Analysis by [email protected]

    Jan. 23, 2023

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
    Changed Reference Type https://github.com/flarum/framework/commit/12f14112a0ecd1484d97330b82beb2a145919015 No Types Assigned https://github.com/flarum/framework/commit/12f14112a0ecd1484d97330b82beb2a145919015 Patch, Third Party Advisory
    Changed Reference Type https://github.com/flarum/framework/releases/tag/v1.6.3 No Types Assigned https://github.com/flarum/framework/releases/tag/v1.6.3 Release Notes, Third Party Advisory
    Changed Reference Type https://github.com/flarum/framework/security/advisories/GHSA-hph3-hv3c-7725 No Types Assigned https://github.com/flarum/framework/security/advisories/GHSA-hph3-hv3c-7725 Mitigation, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:flarum:flarum:*:*:*:*:*:*:*:* versions from (including) 1.3.0 up to (excluding) 1.6.2
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2023-22489 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2023-22489 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.07 }} 0.00%

score

0.30337

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability