Detections
Analytics

Xen: A transaction conflict can crash C Xenstored (XSA-440)

medium Nessus Plugin ID 182974

Language:

Synopsis

The remote Xen hypervisor installation is missing a security update.

Description

When a transaction is committed, C Xenstored will first check the quota is correct before attempting to commit any nodes. It would be possible that accounting is temporarily negative if a node has been removed outside of the transaction.

Unfortunately, some versions of C Xenstored are assuming that the quota cannot be negative and are using assert() to confirm it. This will lead to C Xenstored crash when tools are built without -DNDEBUG (this is the default).

A malicious guest could craft a transaction that will hit the C Xenstored bug and crash it. This will result to the inability to perform any further domain administration like starting new guests, or adding/removing resources to or from any existing guest.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Apply the appropriate patch according to the vendor advisory.

See Also

https://xenbits.xen.org/xsa/advisory-440.html

Plugin Details

Severity: Medium

ID: 182974

File Name: xen_server_XSA-440.nasl

Version: 1.5

Type: local

Family: Misc.

Published: 10/12/2023

Updated: 1/15/2024

Configuration: Enable paranoid mode

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

CVSS Score Source: CVE-2023-34323

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:xen:xen

Required KB Items: Settings/ParanoidReport, installed_sw/Xen Hypervisor

Exploit Ease: No known exploits are available

Patch Publication Date: 10/10/2023

Vulnerability Publication Date: 10/10/2023

Reference Information

CVE: CVE-2023-34323

IAVB: 2023-B-0081-S