Vulnerability · Published Sep 21, 2023 · Assigned by ASRG
CVE-2023-43632Freely Allocate Buffer on The Stack With Data From Socket
Critical 9.0
In plain English
A critical-severity security flaw in EVE OS from LF-Edge, Zededa. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/lf-edge/eve | 0.0.0-20230519072751-977f42b07fa9 | GHSA-6jp5-grgh-jw42 |
| Go | github.com/lf-edge/eve | 0.0.0-20230519072751-977f42b07fa9 | GO-2026-4422 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| LF-Edge, Zededa | EVE OS | 3.0.0 – before 9.5.0 |
Weakness: CWE-789 · Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H