CVE-2026-6458 (GCVE-0-2026-6458)
Vulnerability from cvelistv5 – Published: 2026-06-23 23:49 – Updated: 2026-06-24 13:15 X_Open Source
VLAI
EPSS
VEX
Title
AES-256-GCM Authentication Tag Does Not Cover First Ciphertext Blocks When AAD Is Empty
Summary
Missing cryptographic step in Caliptra Core Firmware (aes_256_gcm_update module) results in an incorrect GCM authentication tag. When the streaming AES-256-GCM API is used with empty AAD, the hardware GHASH accumulator state is not saved after the first update call, causing the final tag to exclude the first batch of processed ciphertext. Ciphertext produced by that call may be modified without the tag reflecting the change.
This issue affects Core Runtime Firmware: from 2.0.0 through 2.0.1, 2.1.0.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-24 13:14 UTC
CWE
- CWE-325 - Missing Cryptographic Step
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| 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) |
guessed |
Date Public
2026-06-23 19:00
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vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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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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Related by attack behaviour
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