CVE-2020-8918

An improperly initialized 'migrationAuth' value in Google's go-tpm TPM1.2 library versions prior to 0.3.0 can lead an eavesdropping attacker to discover the auth value for a key created with CreateWrapKey. An attacker listening in on the channel can collect both 'encUsageAuth' and 'encMigrationAuth', and then can calculate 'usageAuth ^ encMigrationAuth' as the 'migrationAuth' can be guessed for all keys created with CreateWrapKey. TPM2.0 is not impacted by this. We recommend updating your library to 0.3.0 or later, or, if you cannot update, to call CreateWrapKey with a random 20-byte value for 'migrationAuth'.

CVSS v3 6.3 MEDIUM
CVSS v2.0 3.6 LOW

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

3.6^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:P/I:P/A:N

Exploitability : 3.9 / Impact : 4.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://github.com/google/go-tpm/security/advisories/GHSA-5x29-3hr9-6wpw	Exploit Third Party Advisory
https://github.com/google/go-tpm/security/advisories/GHSA-5x29-3hr9-6wpw	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:google:go-tpm:*:*:*:*:*:*:*:*

History

21 Nov 2024, 05:39

Type	Values Removed	Values Added
CVSS	v2 : ~~3.6~~ v3 : ~~7.1~~	v2 : 3.6 v3 : 6.3
References	~~() https://github.com/google/go-tpm/security/advisories/GHSA-5x29-3hr9-6wpw - Exploit, Third Party Advisory~~	() https://github.com/google/go-tpm/security/advisories/GHSA-5x29-3hr9-6wpw - Exploit, Third Party Advisory

Information

Published : 2020-08-11 19:15

Updated : 2024-11-21 05:39

NVD link : CVE-2020-8918

Mitre link : CVE-2020-8918

CVE.ORG link : CVE-2020-8918

JSON object : View

Products Affected

google

go-tpm

CWE

CWE-665

Improper Initialization

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