ID CVE-2022-23039
Summary Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backends in ways being subject to race conditions, resulting in potential data leaks, data corruption by malicious backends, and denial of service triggered by malicious backends: blkfront, netfront, scsifront and the gntalloc driver are testing whether a grant reference is still in use. If this is not the case, they assume that a following removal of the granted access will always succeed, which is not true in case the backend has mapped the granted page between those two operations. As a result the backend can keep access to the memory page of the guest no matter how the page will be used after the frontend I/O has finished. The xenbus driver has a similar problem, as it doesn't check the success of removing the granted access of a shared ring buffer. blkfront: CVE-2022-23036 netfront: CVE-2022-23037 scsifront: CVE-2022-23038 gntalloc: CVE-2022-23039 xenbus: CVE-2022-23040 blkfront, netfront, scsifront, usbfront, dmabuf, xenbus, 9p, kbdfront, and pvcalls are using a functionality to delay freeing a grant reference until it is no longer in use, but the freeing of the related data page is not synchronized with dropping the granted access. As a result the backend can keep access to the memory page even after it has been freed and then re-used for a different purpose. CVE-2022-23041 netfront will fail a BUG_ON() assertion if it fails to revoke access in the rx path. This will result in a Denial of Service (DoS) situation of the guest which can be triggered by the backend. CVE-2022-23042
References
Vulnerable Configurations
  • cpe:2.3:o:xen:xen:-:*:*:*:*:*:*:*
    cpe:2.3:o:xen:xen:-:*:*:*:*:*:*:*
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
    cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
CVSS
Base: 4.4 (as of 29-11-2022 - 02:33)
Impact:
Exploitability:
CWE CWE-362
CAPEC
  • Leveraging Race Conditions
    The adversary targets a race condition occurring when multiple processes access and manipulate the same resource concurrently, and the outcome of the execution depends on the particular order in which the access takes place. The adversary can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance, a race condition can occur while accessing a file: the adversary can trick the system by replacing the original file with his version and cause the system to read the malicious file.
  • Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions
    This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. A typical example is file access. The adversary can leverage a file access race condition by "running the race", meaning that they would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the adversary could replace or modify the file, causing the application to behave unexpectedly.
Access
VectorComplexityAuthentication
LOCAL MEDIUM NONE
Impact
ConfidentialityIntegrityAvailability
PARTIAL PARTIAL PARTIAL
cvss-vector via4 AV:L/AC:M/Au:N/C:P/I:P/A:P
Last major update 29-11-2022 - 02:33
Published 10-03-2022 - 20:15
Last modified 29-11-2022 - 02:33
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