CVE-2021-3565

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.

Weakness

The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.

Affected Software

Potential Mitigations

• Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• For example, in Java, if the programmer does not explicitly initialize a variable, then the code could produce a compile-time error (if the variable is local) or automatically initialize the variable to the default value for the variable’s type. In Perl, if explicit initialization is not performed, then a default value of undef is assigned, which is interpreted as 0, false, or an equivalent value depending on the context in which the variable is accessed.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/29.html

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/