← Vulnerability feed

Vulnerability record · CVE-2025-21355 · published 19 February 2025

CVE-2025-21355: Microsoft bing missing authentication for critical function vulnerability

Microsoft · Bing

Missing Authentication for Critical Function in Microsoft Bing allows an unauthorized attacker to execute code over a network

9.8 CVSS 3.1 Critical EPSS 1.7% · top 23.8% CWE-306 · Missing authentication for critical function
9.8CVSS 3.1 base score
1.7%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
17 Jun 2026Last modified by NVD

Description

Missing Authentication for Critical Function in Microsoft Bing allows an unauthorized attacker to execute code over a network

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21355 PatchVendor Advisory

Track CVE-2025-21355 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2026-33819Microsoft bing deserialization of untrusted data vulnerabilityDeserialization of untrusted data in Microsoft Bing allows an unauthorized attacker to execute code over a network.EPSS 1.5%9.8CVE-2026-32186Microsoft bing server-side request forgery (ssrf) vulnerabilityServer-side request forgery (ssrf) in Microsoft Bing allows an unauthorized attacker to elevate privileges over a network.EPSS 0.90%7.5CVE-2026-26120Microsoft bing server-side request forgery (ssrf) vulnerabilityServer-side request forgery (ssrf) in Microsoft Bing allows an unauthorized attacker to perform tampering over a network.EPSS 0.80%6.8CVE-2014-1670Microsoft bing code injection vulnerabilityThe Microsoft Bing application before 4.2.1 for Android allows remote attackers to install arbitrary APK files via vectors involving a crafted DNS re…EPSS 14%6.5CVE-2020-1329Microsoft bing authentication bypass by spoofing vulnerabilityA spoofing vulnerability exists when Microsoft Bing Search for Android improperly handles specific HTML content, aka 'Microsoft Bing Search Spoofing …EPSS 2.6%4.7CVE-2021-33753Microsoft bing vulnerabilityMicrosoft Bing Search Spoofing VulnerabilityEPSS 1.9%4.3CVE-2026-45650Microsoft bing vulnerabilityUser interface (ui) misrepresentation of critical information in Microsoft Bing allows an unauthorized attacker to perform spoofing over a network.EPSS 0.70%8.8CVE-2026-67277MikroTik RouterOS btest missing authentication leaks kernel memory and crashes kernelRouterOS accepts a "related" btest connection before the primary session is authenticated, letting an unauthenticated client start an IPv4 UDP test. …KEVEPSS 1.6%analysed

Source: NIST National Vulnerability Database (record CVE-2025-21355), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.