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High MSRC-CVE-2023-35391 1 CVE

ASP.NET Core SignalR and Visual Studio Information Disclosure Vulnerability

Published Aug 8, 2023 · Updated Oct 17, 2023 · Revision 2

Summary

Impact: Information Disclosure. Microsoft rating: Important. Not known to be exploited — Exploitation Less Likely. Customer action: Required.

Details

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.

Security updates
17.2.18 — https://docs.microsoft.com/en-us/visualstudio/releases/2022/release-notes
17.4.10 — https://learn.microsoft.com/en-us/visualstudio/releases/2022/release-notes
2.1.40 — https://github.com/dotnet/announcements/issues/XXX
6.0.21 — https://support.microsoft.com/help/5029688
7.0.10 — https://support.microsoft.com/help/5029689

Vulnerabilities 1

Revision history

  1. #2

    Updated one or more CVSS scores for the affected products and added an FAQ explaining the vector string settings. This is an informational change only.

  2. #1

    Information published.

References