Critical severity · published Sep 21, 2023
CVE-2023-43632
As noted in the “VTPM.md” file in the eve documentation, “VTPM is a server listening on port 8877 in EVE, exposing limited functionality of the TPM to the clients
9.9
CVSS
0.7%
EPSS
No
On KEV
Description
As noted in the “VTPM.md” file in the eve documentation, “VTPM is a server listening on port
8877 in EVE, exposing limited functionality of the TPM to the clients.
VTPM allows clients to
execute tpm2-tools binaries from a list of hardcoded options”
The communication with this server is done using protobuf, and the data is comprised of 2
parts:
1. Header
2. Data
When a connection is made, the server is waiting for 4 bytes of data, which will be the header,
and these 4 bytes would be parsed as uint32 size of the actual data to come.
Then, in the function “handleRequest” this size is then used in order to allocate a payload on
the stack for the incoming data.
As this payload is allocated on the stack, this will allow overflowing the stack size allocated for
the relevant process with freely controlled data.
* An attacker can crash the system.
* An attacker can gain control over the system, specifically on the “vtpm_server” process
which has very high privileges.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EV
Edge Virtualization Engine · Linuxfoundation
3.0.0 before 9.5.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-43632
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-43632
asrg.io
https://asrg.io/security-advisories/cve-2023-43632/
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