XAPI open file limit DoS It is possible for an unauthenticated client on the network to cause XAPI to hit its file-descriptor limit. This causes XAPI to be unable to accept new requests for other (trusted) clients, and blocks XAPI from carrying out any tasks that require the opening of file descriptors.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - Xenstore: Guests can get access to Xenstore nodes of deleted domains Access rights of Xenstore nodes are
    per domid. When a domain is gone, there might be Xenstore nodes left with access rights containing the
    domid of the removed domain. This is normally no problem, as those access right entries will be corrected
    when such a node is written later. There is a small time window when a new domain is created, where the
    access rights of a past domain with the same domid as the new one will be regarded to be still valid,
    leading to the new domain being able to get access to a node which was meant to be accessible by the
    removed domain. For this to happen another domain needs to write the node before the newly created domain
    is being introduced to Xenstore by dom0. (CVE-2022-42320)

  - P2M pool freeing may take excessively long The P2M pool backing second level address translation for
    guests may be of significant size. Therefore its freeing may take more time than is reasonable without
    intermediate preemption checks. Such checking for the need to preempt was so far missing. (CVE-2022-33746)

  - Arm: unbounded memory consumption for 2nd-level page tables Certain actions require e.g. removing pages
    from a guest's P2M (Physical-to-Machine) mapping. When large pages are in use to map guest pages in the
    2nd-stage page tables, such a removal operation may incur a memory allocation (to replace a large mapping
    with individual smaller ones). These memory allocations are taken from the global memory pool. A malicious
    guest might be able to cause the global memory pool to be exhausted by manipulating its own P2M mappings.
    (CVE-2022-33747)

  - lock order inversion in transitive grant copy handling As part of XSA-226 a missing cleanup call was
    inserted on an error handling path. While doing so, locking requirements were not paid attention to. As a
    result two cooperating guests granting each other transitive grants can cause locks to be acquired nested
    within one another, but in respectively opposite order. With suitable timing between the involved grant
    copy operations this may result in the locking up of a CPU. (CVE-2022-33748)

  - XAPI open file limit DoS It is possible for an unauthenticated client on the network to cause XAPI to hit
    its file-descriptor limit. This causes XAPI to be unable to accept new requests for other (trusted)
    clients, and blocks XAPI from carrying out any tasks that require the opening of file descriptors.
    (CVE-2022-33749)

The remote host is affected by the vulnerability described in GLSA-202402-07 (Xen: Multiple Vulnerabilities)

    Multiple vulnerabilities have been discovered in Xen. Please review the CVE identifiers referenced below     for details.

Tenable has extracted the preceding description block directly from the Gentoo Linux security advisory.

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

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - network backend may cause Linux netfront to use freed SKBs While adding logic to support XDP (eXpress Data
    Path), a code label was moved in a way allowing for SKBs having references (pointers) retained for further
    processing to nevertheless be freed. (CVE-2022-33743)

  - IBPB may not prevent return branch predictions from being specified by pre-IBPB branch targets leading to
    a potential information disclosure. (CVE-2022-23824)

  - Arm guests can cause Dom0 DoS via PV devices When mapping pages of guests on Arm, dom0 is using an rbtree
    to keep track of the foreign mappings. Updating of that rbtree is not always done completely with the
    related lock held, resulting in a small race window, which can be used by unprivileged guests via PV
    devices to cause inconsistencies of the rbtree. These inconsistencies can lead to Denial of Service (DoS)
    of dom0, e.g. by causing crashes or the inability to perform further mappings of other guests' memory
    pages. (CVE-2022-33744)

  - P2M pool freeing may take excessively long The P2M pool backing second level address translation for
    guests may be of significant size. Therefore its freeing may take more time than is reasonable without
    intermediate preemption checks. Such checking for the need to preempt was so far missing. (CVE-2022-33746)

ID	Name	Product	Family	Type	Severity
424685	Alpine: multiple xen packages: security update to 4.17.0-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	Local	high
424685	Alpine: multiple xen packages: security update to 4.17.0-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	Local	high
189976	GLSA-202402-07 : Xen: Multiple Vulnerabilities	Nessus	Gentoo Local Security Checks	Local	high
407821	Alpine: xen: security update to 4.15.4-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	Local	high
407821	Alpine: xen: security update to 4.15.4-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	Local	high

Detections

Analytics

CVE-2022-33749

medium

Tenable Plugins

high

high

high

high

high