How severe is CVE-2026-6023?

CVE-2026-6023 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-6023 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-6023?

CVE-2026-6023 affects Progress Telerik Ui For Asp.net Ajax. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-6023?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-6023 have an EU (EUVD) identifier?

Yes. CVE-2026-6023 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24632.

When was CVE-2026-6023 published?

CVE-2026-6023 was published on 2026-04-22 and last updated on 2026-06-17.

CVE-2026-6023

CVE-2026-6023 is a high-severity vulnerability in Progress Telerik Ui For Asp.net Ajax with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24632
Weakness: CWE-502
Affected product: Progress Telerik Ui For Asp.net Ajax
Published: 2026-04-22
Last modified: 2026-06-17

Description

In Progress® Telerik® UI for AJAX versions 2024.4.1114 through 2026.1.421, the RadFilter control is vulnerable to insecure deserialization when restoring filter state if the state is exposed to the client. If an attacker tampers with this state, a server-side remote code execution is possible.

Frequently asked questions

What is CVE-2026-6023?: In Progress® Telerik® UI for AJAX versions 2024.4.1114 through 2026.1.421, the RadFilter control is vulnerable to insecure deserialization when restoring filter state if the state is exposed to the client. If an attacker tampers with this state, a server-side remote code execution is possible.
How severe is CVE-2026-6023?: CVE-2026-6023 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-6023 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-6023?: CVE-2026-6023 affects Progress Telerik Ui For Asp.net Ajax. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-6023?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-6023 have an EU (EUVD) identifier?: Yes. CVE-2026-6023 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24632.
When was CVE-2026-6023 published?: CVE-2026-6023 was published on 2026-04-22 and last updated on 2026-06-17.

References

https://www.telerik.com/products/aspnet-ajax/documentation/knowledge-base/kb-security-deserialization-of-untrusted-data-cve-2026-6023

Affected products (1)

cpe:2.3:a:progress:telerik_ui_for_asp.net_ajax:*:*:*:*:*:*:*:*

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