CVE-2021-3565

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-04 · updated 2026-06-17
Weakness: CWE-665

Description

A flaw was found in tpm2-tools in versions before 5.1.1 and before 4.3.2. tpm2_import used a fixed AES key for the inner wrapper, potentially allowing a MITM attacker to unwrap the inner portion and reveal the key being imported. The highest threat from this vulnerability is to data confidentiality.

Affected products

Fedoraproject Fedora: 33, 34
Red Hat Enterprise Linux: 8.0
tpm2-software tpm2-tools: before 4.3.2; from 5.1 before 5.1.1 — fixed in 4.3.2, 5.1.1

How to fix

Upgrade to a fixed version: tpm2-software tpm2-tools 4.3.2, 5.1.1. Check the vendor advisory for mitigations.

References

https://bugzilla.redhat.com/show_bug.cgi?id=1964427
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ESY6HRYUKR5ZG2K5QAJQC5S6HMKZMFK7/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XK5M7I66PBXSN663TSLAZ3V6TWWFCV7C/
https://bugzilla.redhat.com/show_bug.cgi?id=1964427
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ESY6HRYUKR5ZG2K5QAJQC5S6HMKZMFK7/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XK5M7I66PBXSN663TSLAZ3V6TWWFCV7C/

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