CVE-2021-31957
No known exploitation. EPSS puts it in the 92nd 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
ASP.NET Core Denial of Service Vulnerability
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
5.1% chance of exploitation activity in the next 30 days, which ranks it in the 92nd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 1843 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
- Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3)DevTools & CI / ide-editor
- Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6)Operating Systems / windows
- Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8)DevTools & CI / ide-editor
- Microsoft Visual Studio 2019 version 16.10 (includes 16.0 - 16.9)Operating Systems / windows
- Visual Studio 2019 for Mac version 8.10DevTools & CI / ide-editor
- .NET Core 3.1OSS Libraries / generic-library
- .NET 5.0Operating Systems / windows
- .NET CoreOSS Libraries / generic-library
And 5 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Scored 5.9 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
References in the record
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31957
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PMHWHRRYDHKM6BIINW5V7OCSW4SDWB4W/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4PRVVLXXQEF4SEJOBV3VRJHGX7YHY2CG/
And 13 more references. See all after sign-in
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