How severe is CVE-2021-45450?

CVE-2021-45450 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-45450 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45450?

CVE-2021-45450 primarily affects Trustedfirmware Mbed Tls. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-45450?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-45450 published?

CVE-2021-45450 was published on 2021-12-21 and last updated on 2026-06-17.

CVE-2021-45450

CVE-2021-45450 is a high-severity vulnerability in Trustedfirmware Mbed Tls with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-327.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-327
Affected product: Trustedfirmware Mbed Tls
Published: 2021-12-21
Last modified: 2026-06-17

Description

In Mbed TLS before 2.28.0 and 3.x before 3.1.0, psa_cipher_generate_iv and psa_cipher_encrypt allow policy bypass or oracle-based decryption when the output buffer is at memory locations accessible to an untrusted application.

Frequently asked questions

What is CVE-2021-45450?: In Mbed TLS before 2.28.0 and 3.x before 3.1.0, psa_cipher_generate_iv and psa_cipher_encrypt allow policy bypass or oracle-based decryption when the output buffer is at memory locations accessible to an untrusted application.
How severe is CVE-2021-45450?: CVE-2021-45450 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-45450 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45450?: CVE-2021-45450 primarily affects Trustedfirmware Mbed Tls. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-45450?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-45450 published?: CVE-2021-45450 was published on 2021-12-21 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:trustedfirmware:mbed_tls:*:*:*:*:*:*:*:*
cpe:2.3:a:trustedfirmware:mbed_tls:3.0.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*

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