Cyber Resilience

CVE-2019-18935

RCE in Telerik Ui For Asp.Net Ajax 2011.1.315 – 2020.1.114

CISA KEVActive ExploitationEUVD ExploitedPublic PoCRansomware-linkedRCEDeserialization
Published
11 December 2019
Modified
07 November 2025
KEV Added
03 November 2021
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.99 100.0th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2019-18935 is a critical-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Telerik Ui For Asp.Net Ajax. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 0.0% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Progress Telerik UI for ASP.NET AJAX through version 2019.3.1023 contains a .NET deserialization vulnerability in the RadAsyncUpload function, tracked as CVE-2019-18935 and assigned CWE-502. The flaw permits remote code execution when the component's encryption keys are known, which can occur through prior issues such as CVE-2017-11317 or CVE-2017-11357 or by other means. The vulnerability received a CVSS 3.1 base score of 9.8, reflecting network-accessible exploitation with no required privileges or user interaction.

An attacker who can reach the affected RadAsyncUpload endpoint and possesses the encryption keys can supply a malicious serialized object that the server deserializes, resulting in arbitrary code execution on the underlying system. Public exploit code and technical write-ups demonstrate practical attack chains that leverage this deserialization path once key material is obtained.

Later releases address the issue through configuration changes: version 2020.1.114 introduces a default setting that blocks the exploit, while 2019.3.1023 added a non-default setting that can prevent exploitation in that specific release. Public repositories and proof-of-concept materials, including cryptographic tooling and deserialization payloads targeting RadAsyncUpload, have been published that illustrate the attack requirements and impact.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Progress Telerik UI for ASP.NET AJAX through 2019.3.1023 contains a .NET deserialization vulnerability in the RadAsyncUpload function. This is exploitable when the encryption keys are known due to the presence of CVE-2017-11317 or CVE-2017-11357, or other means. Exploitation can result…

more

in remote code execution. (As of 2020.1.114, a default setting prevents the exploit. In 2019.3.1023, but not earlier versions, a non-default setting can prevent exploitation.)

CWE(s)
KEV Date Added
03 November 2021

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2017-11317Same product: Telerik Ui For Asp.Net Ajaxboth on KEV
CVE-2024-10095Same vendor: Telerik
CVE-2024-10012Same vendor: Telerik
CVE-2024-7576Same vendor: Telerik
CVE-2024-8316Same vendor: Telerik
CVE-2025-55182Shared CWE-502both on KEV
CVE-2018-1000861Shared CWE-502both on KEV
CVE-2026-45247Shared CWE-502both on KEV
CVE-2026-20963Shared CWE-502both on KEV
CVE-2017-3066Shared CWE-502both on KEV

Affected Assets

telerik
ui for asp.net ajax
2011.1.315 — 2020.1.114

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-502

Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.

addresses: CWE-502

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-502

Validates or rejects untrusted serialized data before deserialization occurs.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

addresses: CWE-502

Provenance of associated data allows detection of untrusted sources before deserialization or processing occurs.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-02 none match
prevents

PR.PS-02 addresses only post-deployment updates/patching and cannot prevent introduction of unsafe deserialization code, yet it can remediate some instances when the flaw exists in outdated libraries or components.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing includes validation of deserialization routines and the use of untrusted data, reducing the likelihood that unsafe object reconstruction will be deployed.

prevents

Requiring vetted libraries, regular updates and SAST before release reduces the likelihood that deserialization logic will accept and act on attacker-controlled serialized objects.

finds

Regular scanning of third-party libraries and timely patching reduce the likelihood that unsafe deserialization vulnerabilities remain active.

none

Mandatory malware scanning of data received over networks or storage media intercepts malicious serialized payloads before they are deserialized by the target application.

References