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CVE-2026-40968 (GCVE-0-2026-40968)

Vulnerability from cvelistv5 – Published: 2026-04-28 13:42 – Updated: 2026-04-28 14:36
VLAI
Title
Spring gRPC SecurityContext leaks across requests on authorization failure
Summary
When an authenticated user is denied access to a gRPC method, their authenticated identity remains bound to the gRPC worker thread and can be inherited by a subsequent unauthenticated request on the same thread. This may allow the subsequent user to gain escalated permissions. Affected versions: Spring gRPC: 1.0.0 - 1.0.2 (fixed in 1.0.3). Older, unsupported versions are also affected.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-28 14:36 UTC
CWE
  • CWE-653 - Improper Isolation or Compartmentalization
Assigner
References
Impacted products
Vendor Product Version CPE status
Spring Spring gRPC Affected: 1.0.0 , < 1.0.3 (custom)
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.

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.
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