# CVE-2026-124699: Improper Control of Generation of Code in Progress Telerik UI for WinForms

Status: published. Published: 2026-11-12. Updated: 2026-11-12.

In Telerik UI for WinForms, versions prior to 2026.4.1111, an improper control of code generation vulnerability exists that allows an attacker to supply a crafted expression and execute unauthorized code in the context of the affected application.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Progress Software / Telerik UI for WinForms: ≥ 2026.3.1007; < 2026.4.1111 (affected, custom). Source: CNA: ProgressSoftware

## Severity and prioritization

- CVSS 3.1: 7.8 (high); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H; source: CNA: ProgressSoftware

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-94

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.telerik.com/products/winforms/documentation/knowledge-base/kb-security-improper-control-of-generation-of-code-cve-2026-124699 (CNA: ProgressSoftware; vendor-advisory)

## Provenance

- CNA: ProgressSoftware: https://www.cve.org/CVERecord?id=CVE-2026-124699; retrieved 2026-11-12; source updated 2026-11-12

Revision: 891c97f29fb7f0b658c36cea7d3ee6eab3db0a466d0058010dba35e619567b28

Canonical: https://y2.dev/cve/CVE-2026-124699

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