CVE-2026-40379 (GCVE-0-2026-40379)

Vulnerability from cvelistv5 – Published: 2026-05-12 16:58 – Updated: 2026-05-13 17:58 Exclusively Hosted Service
VLAI?
Title
Microsoft Enterprise Security Token Service (ESTS) Spoofing Vulnerability
Summary
Exposure of sensitive information to an unauthorized actor in Azure Entra ID allows an unauthorized attacker to perform spoofing over a network.
Severity ?
9.3 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N/E:U/RL:O/RC:C
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
References
Impacted products
Date Public ?
2026-05-07 14:00
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.