CVE-2020-8918: google llc google/go-tpm library Improper Initialization
Vulnerability summary
CVE-2020-8918 is a high (CVSS 7.1) Improper Initialization vulnerability in google llc google/go-tpm library. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 7% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 11-08-2020PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
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 metrics
4 scores · 3 sources · 2 versions- CVE.orgCNA6.3MediumCVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:NDiffers
- OSV · GoEcosystem advisory · calculated7.1HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS trend
Probability
0.18%
Chance of exploitation in the next 30 days
Percentile
7%
Versus all other CVEs
30-day change
0.00 pp
From 0.18% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundGo Tpm
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Github.com/google1 product
- go-tpm< 0.3.0
Google1 product
- go-tpm< 0.3.0
Google llc1 product
- google/go-tpm library≥ stable, < 0.3.0
3 vendors · 3 products
References
6 links- github.com/google/go-tpm/security/advisories/GHSA-5x29-3hr9-6wpwX Refsource CONFIRMWEBExploitThird Party Advisory
- github.com/google/go-tpmPACKAGE