# CVE-2026-33819: Deserialization of untrusted data in Microsoft Bing allows an unauthorized attacker to execute code over a network.

Source: https://junglewise.ai/threats/cve-2026-33819-deserialization-of-untrusted-data-in-microsoft-bing-allows-an  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-23  
License: CC BY 4.0 with a link back

CVE-2026-33819 · Severity: critical · CVSS 10 · Published 2026-04-23

Deserialization of untrusted data in Microsoft Bing allows an unauthorized attacker to execute code over a network.

Technologies: [Microsoft Bing](https://junglewise.ai/threats/technologies/bing). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-33819 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-33819 being exploited in the wild.

**How severe is CVE-2026-33819?** Critical severity, with a CVSS score of 10, published 23 April 2026.

**Which products and versions are affected?** Microsoft Bing. The advisory does not name versions.

**Is there a fix for CVE-2026-33819?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2026-33819?** Check whether you run Microsoft Bing. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Bing

## Related threats

- [Microsoft Bing UI misrepresentation spoofing vulnerability](https://junglewise.ai/threats/cve-2026-45650-microsoft-bing-ui-misrepresentation-spoofing-vulnerability)
- [Microsoft Bing SSRF and elevation of privilege](https://junglewise.ai/threats/cve-2026-32186-microsoft-bing-ssrf-and-elevation-of-privilege)