CVE-2021-3446

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-25 · updated 2026-06-17
Weakness: CWE-327

Description

A flaw was found in libtpms in versions before 0.8.2. The commonly used integration of libtpms with OpenSSL contained a vulnerability related to the returned IV (initialization vector) when certain symmetric ciphers were used. Instead of returning the last IV it returned the initial IV to the caller, thus weakening the subsequent encryption and decryption steps. The highest threat from this vulnerability is to data confidentiality.

Affected products

Fedoraproject Fedora: 33
stefanberger libtpms: before 0.8.2 — fixed in 0.8.2
Red Hat Enterprise Linux: 8.0

How to fix

Upgrade to a fixed version: stefanberger libtpms 0.8.2. Check the vendor advisory for mitigations.

References

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