EUVD-2026-56723
GHSA-mvrg-82pf-2wp2
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Network-reachable with no attacker privileges; user action triggers credential exposure; impact confined to limited confidentiality with no integrity or availability effect.
Primary rating from Vendor (microsoft).
CVSS VectorVendor: microsoft
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Lifecycle Timeline
3DescriptionCVE.org
Insufficiently protected credentials in Microsoft Office Outlook allows an unauthorized attacker to perform spoofing over a network.
AnalysisAI
Insufficiently protected credentials in Microsoft Office Outlook expose authentication material over network connections, enabling unauthenticated network-positioned attackers to perform spoofing attacks contingent on victim user interaction. The flaw affects Outlook 2016, Office 2019, Office LTSC 2021, Office LTSC 2024, and Microsoft 365 Apps for Enterprise - collectively spanning nearly the entire current Outlook product line. …
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Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | User interaction is required (CVSS UI:R): the victim must perform an action in Outlook - such as sending or receiving email, or Outlook automatically connecting to check mail - that triggers the vulnerable authentication exchange. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 3.1 base score of 4.3 (Medium) reflects a constrained but realistic threat: network-reachable, low complexity, no attacker privileges required, but limited to confidentiality impact (C:L) with no integrity or availability effect, and requiring user interaction (UI:R). … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker with a network man-in-the-middle position - for example via ARP poisoning on a local segment or a rogue Wi-Fi access point - waits for a victim to open Outlook and initiate a mail server connection. The authentication exchange transmits credentials in an insufficiently protected form, which the attacker captures. … |
| Remediation | Apply the vendor-released patch without delay. … Detailed patch versions, workarounds, and compensating controls in full report. |
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Same weakness CWE-522 – Insufficiently Protected Credentials
View allSame technique Authentication Bypass
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External POC / Exploit Code
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