Common Weakness Enumeration

CWE-253

Incorrect Check of Function Return Value

The product incorrectly checks a return value from a function, which prevents it from detecting errors or exceptional conditions.

CVE-2026-5818 (GCVE-0-2026-5818)

Vulnerability from cvelistv5 – Published: 2026-06-23 23:50 – Updated: 2026-06-24 13:04 X_Open Source
VLAI
Title
MCU Firmware Update Authentication Bypass on Caliptra Core
Summary
Incorrect check of function return value in Caliptra Core Runtime Firmware (ActivateFirmwareCmd::activate_fw modules) allows bypass of Caliptra Core's verification of the MCU FW during a hitless update. This issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-253 - Incorrect check of function return value
Assigner
Impacted products
Vendor Product Version
Caliptra Core Runtime Firmware Affected: 2.0.0 , ≤ 2.0.1 (semver)
Affected: 2.1.0 (semver)
Unaffected: 2.0.2 (semver)
Unaffected: 2.1.1 (semver)
Create a notification for this product.
Date Public
2026-06-23 19:00
Credits
NVIDIA Offensive Security Research (OSR) team
Show details on NVD website

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Mitigation

Phase: Architecture and Design

Strategy: Language Selection

Description:

  • Use a language or compiler that uses exceptions and requires the catching of those exceptions.
Mitigation

Phase: Implementation

Description:

  • Properly check all functions which return a value.
Mitigation

Phase: Implementation

Description:

  • When designing any function make sure you return a value or throw an exception in case of an error.

No CAPEC attack patterns related to this CWE.

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