CVE-2026-54998 (GCVE-0-2026-54998)

Vulnerability from cvelistv5 – Published: 2026-07-02 22:18 – Updated: 2026-07-02 22:18 Exclusively Hosted Service
VLAI
Title
Microsoft Exchange Online Elevation of Privilege Vulnerability
Summary
Incorrect authorization in Microsoft Exchange Online allows an authorized attacker to elevate privileges over a network.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
CWE
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Date Public
2026-07-02 14:00
Show details on NVD website
To clipboard 

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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

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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.