CVE-2026-90447 (GCVE-0-2026-90447)
Vulnerability from cvelistv5 – Published: 2026-09-11 21:48 – Updated: 2026-10-02 21:12
VLAI
EPSS
VEX
Title
Authentication Bypass by Spoofing in Malcolm
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.
Severity
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
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://raw.githubusercontent.com/cisagov/CSAF/de… | government-resourcevendor-advisory |
| https://www.cisa.gov/news-events/ics-advisories/i… |
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Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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They have not been verified by an analyst and are provided for guidance only.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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