CVE-2021-3505
Publication date 19 April 2021
Last updated 25 August 2025
Ubuntu priority
Description
A flaw was found in libtpms in versions before 0.8.0. The TPM 2 implementation returns 2048 bit keys with ~1984 bit strength due to a bug in the TCG specification. The bug is in the key creation algorithm in RsaAdjustPrimeCandidate(), which is called before the prime number check. The highest threat from this vulnerability is to data confidentiality.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libtpms | ||
| 20.04 LTS focal | Not in release | |
| 18.04 LTS bionic | Not in release | |
| 16.04 LTS xenial | Not in release | |
| 14.04 LTS trusty | Not in release |
Severity score breakdown
CVSS version: CVSS v3.0
Base score
5.5 · Medium
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
References
Other references
- https://github.com/stefanberger/libtpms/issues/183
- https://github.com/stefanberger/libtpms/commit/625171be0c8225824740b5d0fb7e8562f6a1c6a8 (v0.8.0)
- https://github.com/stefanberger/libtpms/commit/c1f7bf55099fcd427715aa65e130475c6e836a6b (v0.8.0)
- https://bugzilla.redhat.com/show_bug.cgi?id=1950046
- https://www.cve.org/CVERecord?id=CVE-2021-3505