CVE-2017-0247
Public exploit available. Not confirmed exploited in the wild yet. 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
A denial of service vulnerability exists when the ASP.NET Core fails to properly validate web requests. NOTE: Microsoft has not commented on third-party claims that the issue is that the TextEncoder.EncodeCore function in the System.Text.Encodings.Web package in ASP.NET Core Mvc before 1.0.4 and 1.1.x before 1.1.3 allows remote attackers to cause a denial of service by leveraging failure to properly calculate the length of 4-byte characters in the Unicode Non-Character range.
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
1 source with a proof of concept or module.
Exploit links, PoCs and Metasploit modules after sign-in- EPSS
17% chance of exploitation activity in the next 30 days, which ranks it in the 97th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
A public exploit existed 67 days before the patch.
- Patch availablerecord updated
- Public exploit / PoCsource: other
- Publishedweakness classified, att&ck mapped
Affected products
- Microsoft.AspNetCore.MvcOSS Libraries
- Microsoft.AspNetCore.Mvc.CoreOSS Libraries
- System.Net.HttpOSS Libraries
- System.Text.Encodings.WebOSS Libraries
- System.Net.Http.WinHttpHandlerOSS Libraries
- System.Net.SecurityOSS Libraries
- System.Net.WebSockets.ClientOSS Libraries
- Microsoft.AspNetCore.Mvc.AbstractionsOSS Libraries
- asp.net model view controllerOSS Libraries / web-framework
- microsoft.aspnetcore.mvc.abstractionsOperating Systems / windows
- microsoft.aspnetcore.mvc.apiexplorerOperating Systems / windows
- microsoft.aspnetcore.mvc.corsOperating Systems / windows
- microsoft.aspnetcore.mvc.dataannotationsOperating Systems / windows
- microsoft.aspnetcore.mvc.formatters.jsonOperating Systems / windows
- microsoft.aspnetcore.mvc.formatters.xmlOperating Systems / windows
- microsoft.aspnetcore.mvc.localizationOperating Systems / windows
And 21 more affected products. See all after sign-in
Technical detail
CVSS 3.0 vector
Open in the CVSS calculatorCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Scored 7.5 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 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 HighTotal loss of integrity — attacker can modify any data in the component
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1190Exploit Public-Facing Applicationlow confidence
Sources
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