ASP.NET Core SignalR and Visual Studio Information Disclosure Vulnerability

Security Vulnerability

Released: Aug 8, 2023

Last updated: Oct 17, 2023

Assigning CNA
Microsoft
CVE.org link
CVE-2023-35391
Impact
Information Disclosure
Max Severity
Important
CVSS Source
Microsoft
Vector String
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C

Please see Common Vulnerability Scoring System for more information on the definition of these metrics.

Exploitability

The following table provides an exploitability assessment for this vulnerability at the time of original publication.

Publicly disclosed
No
Exploited
No
Exploitability assessment
Exploitation Less Likely

FAQ

What type of information could be disclosed by this vulnerability?

This vulnerability makes it possible to listen to any group or user with a specially crafted group/username. By exploiting this vulnerability, the attacker can now receive messages for group(s) that they are unauthorized to view.

According to the CVSS metric, the attack vector is local (AV:L). Why does the CVE title indicate that this is information disclosure?

The attack itself is carried out locally. For example, when the score indicates that the Attack Vector is Local (AV:L) and User Interaction is Required (UI:R), this could describe an exploit in which an attacker, through social engineering, convinces a victim to download and run a malicious application. This could lead to a local attack on the user's device which could leak data.

Acknowledgements

  • Brennan Conroy
Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgements for more information.

Security Updates

To determine the support lifecycle for your software, see the Microsoft Support Lifecycle.

Release date Descending

Disclaimer

The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

Revisions

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