CVE-2023-22488
Missing authorization in Flarum
No known exploitation. EPSS puts it in the 31st percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
Flarum is a forum software for building communities. Using the notifications feature, one can read restricted/private content and bypass access checks that would be in place for such content. The notification-sending component does not check that the subject of the notification can be seen by the receiver, and proceeds to send notifications through their different channels. The alerts do not leak data despite this as they are listed based on a visibility check, however, emails are still sent out. This means that, for extensions which restrict access to posts, any actor can bypass the restriction by subscribing to the discussion if the Subscriptions extension is enabled. The attack allows the leaking of some posts in the forum database, including posts awaiting approval, posts in tags the user has no access to if they could subscribe to a discussion before it becomes private, and posts restricted by third-party extensions. All Flarum versions prior to v1.6.3 are affected. The vulnerability has been fixed and published as flarum/core v1.6.3. All communities running Flarum should upgrade as soon as possible to v1.6.3. As a workaround, disable the Flarum Subscriptions extension or disable email notifications altogether. There are no other supported workarounds for this issue for Flarum versions below 1.6.3.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.4% chance of exploitation activity in the next 30 days, which ranks it in the 31st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 679 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:N
Scored 6.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
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