Security readout for executives and security teams
Plain-English summary
A remote attacker may tamper with type information accepted by Telerik’s DialogHandler, potentially changing how server-side dialogs are processed. Successful abuse could compromise data confidentiality, integrity, and availability, although exploitation is rated high complexity and may require chaining with other weaknesses.
Executive priority
Treat this as a high-priority remediation for internet-facing deployments. The potential impact is broad, but available evidence indicates exploitation is difficult and does not confirm attacks in the wild. Inventory affected applications promptly and schedule an upgrade based on exposure and data sensitivity.
Technical view
CVE-2026-13187 is a CWE-470 unsafe type-selection issue in Telerik UI for ASP.NET AJAX before v2026.2.708. The CVSS 3.1 vector indicates network reachability without authentication or user interaction, high attack complexity, and potentially high impact across confidentiality, integrity, and availability.
Likely exposure
Applications using a vulnerable Telerik UI for ASP.NET AJAX release and exposing DialogHandler functionality to untrusted networks are the likely concern. The supplied evidence does not identify required configuration, enabled-by-default status, or precise deployment prerequisites.
Exploitation context
The CVSS vector describes remote, unauthenticated access but high exploitation complexity. The description says the flaw may enable chained exploitation. The source bundle marks KEV false and provides no evidence of active exploitation or a public proof of concept.
Researcher notes
The bundle’s prose defines affected releases as prior to v2026.2.708, while its structured affected entry lists only 2011.2.712 with a default status of unaffected. Confirm the authoritative version range with Progress. No configuration prerequisites, technical root-cause detail, exploitation telemetry, or specific indicators of compromise are supplied.
Mitigation direction
- Upgrade Telerik UI for ASP.NET AJAX to v2026.2.708 or later.
- Confirm the selected release is supported and applicable using the vendor advisory.
- If upgrading is delayed, consult Progress for documented temporary mitigations and deployment-specific guidance.
- Prioritize internet-facing applications and systems handling sensitive or business-critical data.
Validation and detection
- Inventory Telerik UI for ASP.NET AJAX versions across deployed applications.
- Verify production assemblies are v2026.2.708 or later after remediation.
- Identify whether DialogHandler functionality is reachable from untrusted networks.
- Review relevant request and application logs for unusual DialogHandler activity.
- Retest application dialog functionality after upgrading.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-470: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-13187 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H2.25.9ProgressSoftwareVulnerability scoring details
Base CVSS 3.1 score
8.1HighVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://www.telerik.com/products/aspnet-ajax/documentation/knowledge-base/kb-security-dialoghandler-provider-type-tampering-CVE-2026-13187CVE reference, ProgressSoftware · vendor-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')
Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.