CVE-2021-3565 [Medium] | Security Vulnerability in Tpm2-Tools

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.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.39%	1.34%	+0.95%
2	2026-03-21	0.16%	0.39%	+0.23%
3	2025-11-13	—	0.16%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.39%

1.34%

+0.95%

2026-03-21

0.16%

0.39%

+0.23%

2025-11-13

—

0.16%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.9	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	2.2	3.6	[email protected]
4.3	2.0	MEDIUM	`AV:N/AC:M/Au:N/C:P/I:N/A:N` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:N) No availability impact.	8.6	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.9

3.1

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

2.2

3.6

[email protected]

4.3

2.0

MEDIUM

AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:N): No availability impact.

8.6

2.9

[email protected]

OS Trackers for CVE-2021-3565

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2021-3565 not yet assigned priority: Debian including 1 source packages (tpm2-tools), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2021-3565
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2021-3565
`suse`	medium	CVE-2021-3565 severity moderate: SUSE including 11 source package names (tpm2-tools-4.1.1-5.el8, tpm2.0-tools, …), 33 product×package rows across 33 product lines (HPE Helion OpenStack 8, SUSE Liberty Linux 8, … (33 product lines)): Known Not Affected 17, Fixed 16.	https://www.suse.com/security/cve/CVE-2021-3565/
`ubuntu`	medium	CVE-2021-3565 medium priority: Ubuntu including 1 source packages (tpm2-tools), 16 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 8, needs-triage 5, DNE 1, needed 1, not-affected 1.	https://ubuntu.com/security/CVE-2021-3565

Affected software / configurations for CVE-2021-3565

Vendor	Product	Version	Raw CPE
tpm2-tools_project	tpm2-tools	< 4.3.2	cpe:2.3:a:tpm2-tools_project:tpm2-tools::::::::
tpm2-tools_project	tpm2-tools	>= 5.1, < 5.1.1	cpe:2.3:a:tpm2-tools_project:tpm2-tools::::::::
redhat	enterprise_linux	8.0	cpe:2.3:o:redhat:enterprise_linux:8.0:::::::*
fedoraproject	fedora	33	cpe:2.3:o:fedoraproject:fedora:33:::::::*
fedoraproject	fedora	34	cpe:2.3:o:fedoraproject:fedora:34:::::::*

References for CVE-2021-3565

URL	Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1964427	Issue Tracking Patch Third Party Advisory
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/

URL

CVE-2021-3565

Exploit prediction scoring system (EPSS) score for CVE-2021-3565

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3565

Weakness enumeration for CVE-2021-3565

OS Trackers for CVE-2021-3565

Affected software / configurations for CVE-2021-3565

References for CVE-2021-3565