cryptodev-linux version 1.14 and prior contain a page reference handling flaw in the get_userbuf function of the /dev/crypto device driver that allows local users to trigger use-after-free conditions. Attackers with access to the /dev/crypto interface can repeatedly decrement reference counts of controlled pages to achieve local privilege escalation.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 4
https://gist.github.com/n4sm/0fd2479e0c23e0fa2f192cd8fda45750
disclosure@vulncheck.com
https://github.com/cryptodev-linux/cryptodev-linux/pull/104
disclosure@vulncheck.com
https://nasm.re/posts/cryptodev-linux-vuln/
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/cryptodev-linux-get-userbuf-use-after-free…
disclosure@vulncheck.com