CVE-2017-9248
CriticalExploitedPublic exploitTelerik.Web.UI.dll in Progress Telerik UI for ASP.NET AJAX before R2 2017 SP1 and Sitefinity before 10.0.6412.0 does not properly protect Telerik.Web.UI.DialogParametersEncryptionKey or the MachineKey, which makes it easier for remote attackers to defeat cryptographic protection…
Published Mar 19, 2021 · Updated Oct 21, 2025
Key Facts
Patch immediately- CVE-2017-9248 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Sitefinity (Progress), Ui For Asp.net Ajax (Telerik).
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 22, 2020. Public exploit code is available.
- EPSS estimates a 75% probability of exploitation in the next 30 days.
- Fixed versions are available, including Sitefinity 10.0.6412.0, Ui For Asp.net Ajax 2017.2.503.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
75%
Higher than 99.5% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2017-9248 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
Telerik.Web.UI.dll in Progress Telerik UI for ASP.NET AJAX before R2 2017 SP1 and Sitefinity before 10.0.6412.0 does not properly protect Telerik.Web.UI.DialogParametersEncryptionKey or the MachineKey, which makes it easier for remote attackers to defeat cryptographic protection mechanisms, leading to a MachineKey leak, arbitrary file uploads or downloads, XSS, or ASP.NET ViewState compromise.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | May 3, 2022 | Not reported |
| Industry KEV feed | Oct 22, 2020 | May 3, 2022 | Not reported |
| CIRCL KEV | Nov 3, 2021 | May 3, 2022 | Not reported |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| SitefinityProgress | See advisory | 10.0.6412.0 |
| Ui For Asp.net AjaxTelerik | See advisory | 2017.2.503 |
Patched Releases
Sitefinity
10.0.6412.0
Ui For Asp.net Ajax
2017.2.503
Timeline
Added to Industry KEV feed
Oct 22, 2020
Publicly disclosed
Mar 19, 2021
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Last updated
Oct 21, 2025
Weakness Type
- CWE-522 Insufficiently Protected Credentials
References
- advisoryhttps://us-cert.cisa.gov/ics
- advisoryhttps://us-cert.cisa.gov/ics/advisories/icsa-21-077-02
- advisoryhttps://us-cert.cisa.gov/report
- advisoryhttps://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- advisoryhttps://www.hitachiabb-powergrids.com/contact-us/
FAQ
Common Questions.
Telerik.Web.UI.dll in Progress Telerik UI for ASP.NET AJAX before R2 2017 SP1 and Sitefinity before 10.0.6412.0 does not properly protect Telerik.Web.UI.DialogParametersEncryptionKey or the MachineKey, which makes it easier for remote attackers to defeat cryptographic protection mechanisms, leading to a MachineKey lea…
Affected: Sitefinity (Progress); Ui For Asp.net Ajax (Telerik). The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 22, 2020.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of May 3, 2022.
Public exploit code is available.
Fixed versions are available, including Sitefinity 10.0.6412.0, Ui For Asp.net Ajax 2017.2.503.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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