Bug 2222903 (CVE-2023-3674)

Summary:	CVE-2023-3674 keylime: Attestation failure when the quote's signature does not validate
Product:	[Other] Security Response	Reporter:	Mauro Matteo Cascella <mcascell>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	ansasaki, dueno, ksrot, pkoncity, scorreia
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	keylime 7.2.5, keylime 7.3.0	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the keylime attestation verifier, which fails to flag a device's submitted TPM quote as faulty when the quote's signature does not validate for some reason. Instead, it will only emit an error in the log without flagging the device as untrusted.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2222908, 2222909
Bug Blocks:	2222904

Description Mauro Matteo Cascella 2023-07-14 12:26:17 UTC

The keylime attestation verifier fails to flag a device's submitted TPM quote as faulty when the quote's signature does not validate for some reason. Instead, it will only emit an error in the log but not flag the device as being untrusted.

To exploit this bug, a non-privileged user would have to modify the keylime agent to create invalid quotes a could then use invalid measurement lists to hide the trust state of a system. He would then have to trick the administrator in using the user's modified keylime agent.

Upstream fix:
https://github.com/keylime/keylime/commit/95ce3d86bd2c53009108ffda2dcf553312d733db

Comment 1 Mauro Matteo Cascella 2023-07-14 12:40:38 UTC

Created keylime tracking bugs for this issue:

Affects: fedora-all [bug 2222908]