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CVE-2026-90447 (GCVE-0-2026-90447)

Vulnerability from cvelistv5 – Published: 2026-09-11 21:48 – Updated: 2026-09-14 16:14
VLAI
Summary
A routing rule selects between two different authentication mechanisms for the same downstream service based on the value of a client-supplied request header, rather than on any property the client cannot control. An authenticated user in possession of a shared service credential can set this header to route around the primary role-based authorization check and reach the alternate path's fixed, elevated role instead. This allows a low-privileged authenticated attacker who knows the shared credential to perform actions reserved for a higher-privileged role.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-14 16:14 UTC
CWE
  • CWE-290 - Authentication bypass by spoofing
References
URL Tags
https://raw.githubusercontent.com/cisagov/CSAF/de… government-resourcevendor-advisory
Impacted products
Vendor Product Version CPE status
CISA Malcolm Affected: 0 , < v26.06.0 (custom)
Unaffected: v26.06.0
guessed Create a notification for this product.
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.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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