Security readout for executives and security teams
Plain-English summary
A vulnerable Telerik persistence feature can treat a forged browser cookie as trusted data. If an internet-facing application uses cookie-based storage with RadPersistenceManager or RadDockLayout, an unauthenticated attacker could potentially run code on the server. Exploitation is rated high complexity, but successful compromise could expose data, alter systems, or disrupt service.
Executive priority
Treat as an urgent remediation for externally reachable applications meeting the feature and version conditions. Request rapid inventory, upgrade planning, and compensating access restrictions. Systems not using the named cookie-storage paths are not shown as exposed by the supplied evidence.
Technical view
Telerik UI for ASP.NET AJAX before v2026.2.708 is vulnerable to CWE-502 when RadPersistenceManager or RadDockLayout uses cookie-based storage. Attacker-controlled cookie content may be deserialized, enabling unauthenticated remote code execution. CVSS 3.1 is 8.1: network-accessible, high complexity, no privileges or user interaction, with high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to applications running a pre-v2026.2.708 release and using cookie-based storage in either named component. Internet-accessible applications present the clearest risk. The bundle’s structured affected-version entry lists only 2013.1.220 and marks other versions unaffected, conflicting with its broader description; inventories should therefore be checked against the vendor advisory.
Exploitation context
The supplied sources do not establish active exploitation, and the CVE is not identified as KEV in the bundle. Exploitation requires no authentication or user interaction but is rated high complexity. No assumptions should be made about public exploit availability or observed attacks without additional evidence.
Researcher notes
The vulnerability is an unsafe deserialization issue in Telerik’s PersistenceFramework cookie path. Scope depends on both component use and storage configuration. The supplied record contains inconsistent version metadata: its description says all releases before v2026.2.708, while the structured affected entry names 2013.1.220 and defaults others to unaffected. Validate scope directly against the vendor advisory.
Mitigation direction
- Upgrade Telerik UI for ASP.NET AJAX to v2026.2.708 or later.
- Prioritize internet-facing applications using RadPersistenceManager or RadDockLayout cookie storage.
- Check the vendor advisory for supported upgrade and configuration guidance.
- Restrict external access to affected applications until remediation is verified.
Validation and detection
- Inventory Telerik UI for ASP.NET AJAX versions across deployed applications.
- Confirm whether RadPersistenceManager or RadDockLayout uses cookie-based storage.
- Verify upgraded deployments report v2026.2.708 or later.
- Review application and endpoint telemetry for suspicious persistence-cookie processing or resulting server activity.
- Reconcile the bundle’s version inconsistency with the current vendor advisory.
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-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-13185 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-persistence-cookie-deserialization-CVE-2026-13185CVE 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.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.