CVE-2021-45451

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-12-21 · updated 2026-06-17
Weakness: CWE-327

Description

In Mbed TLS before 3.1.0, psa_aead_generate_nonce allows policy bypass or oracle-based decryption when the output buffer is at memory locations accessible to an untrusted application.

Affected products

mbedtls: before 3.1.0 — fixed in 3.1.0
Fedoraproject Fedora: 36, 37

How to fix

Upgrade to a fixed version: mbedtls 3.1.0. Check the vendor advisory for mitigations.

References

https://github.com/ARMmbed/mbedtls/releases/tag/v3.1.0
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IL66WKJGXY5AXMTFE7QDMGL3RIBD6PX5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TALJHOYAYSUJTLN6BYGLO4YJGNZUY74W/
https://github.com/ARMmbed/mbedtls/releases/tag/v3.1.0
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IL66WKJGXY5AXMTFE7QDMGL3RIBD6PX5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TALJHOYAYSUJTLN6BYGLO4YJGNZUY74W/

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