How severe is CVE-2026-33819?

CVE-2026-33819 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-33819 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33819?

CVE-2026-33819 affects Microsoft Bing. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-33819?

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

Does CVE-2026-33819 have an EU (EUVD) identifier?

Yes. CVE-2026-33819 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25311.

When was CVE-2026-33819 published?

CVE-2026-33819 was published on 2026-04-23 and last updated on 2026-06-17.

CVE-2026-33819

CVE-2026-33819 is a critical-severity vulnerability in Microsoft Bing with a CVSS 3.x base score of 10.0. 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: Critical (CVSS 3.x base score 10.0)
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-25311
Weakness: CWE-502
Affected product: Microsoft Bing
Published: 2026-04-23
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2026-33819?: Deserialization of untrusted data in Microsoft Bing allows an unauthorized attacker to execute code over a network.
How severe is CVE-2026-33819?: CVE-2026-33819 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-33819 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33819?: CVE-2026-33819 affects Microsoft Bing. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33819?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-33819 have an EU (EUVD) identifier?: Yes. CVE-2026-33819 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25311.
When was CVE-2026-33819 published?: CVE-2026-33819 was published on 2026-04-23 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33819

Affected products (1)

cpe:2.3:a:microsoft:bing:-:*:*:*:*:*:*:*

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