x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virtualization. In AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit guests. With the focus now being on 64-bit systems, and the availability of explicit hardware support for virtualization, fixing speculation issues in ring 1 is not a priority for processor companies. Indirect Branch Restricted Speculation (IBRS) is an architectural x86 extension put together to combat speculative execution sidechannel attacks, including Spectre v2. It was retrofitted in microcode to existing CPUs. For more details on Spectre v2, see: http://xenbits.xen.org/xsa/advisory-254.html However, IBRS does not architecturally protect ring 0 from predictions learnt in ring 1. For more details, see: https://software.intel.com/security-software-guidance/deep-dives/deep-dive-indirect-branch-restricted-speculation Similar situations may exist with other mitigations for other kinds of speculative execution attacks. The situation is quite likely to be similar for speculative execution attacks which have yet to be discovered, disclosed, or mitigated.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in     ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is     why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virtualization. In     AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit     guests. With the focus now being on 64-bit systems, and the availability of explicit hardware support for     virtualization, fixing speculation issues in ring 1 is not a priority for processor companies. Indirect     Branch Restricted Speculation (IBRS) is an architectural x86 extension put together to combat speculative     execution sidechannel attacks, including Spectre v2. It was retrofitted in microcode to existing CPUs. For     more details on Spectre v2, see: http://xenbits.xen.org/xsa/advisory-254.html However, IBRS does not     architecturally protect ring 0 from predictions learnt in ring 1. For more details, see:
    https://software.intel.com/security-software-guidance/deep-dives/deep-dive-indirect-branch-restricted-     speculation Similar situations may exist with other mitigations for other kinds of speculative execution     attacks. The situation is quite likely to be similar for speculative execution attacks which have yet to     be discovered, disclosed, or mitigated. (CVE-2021-28689)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote SUSE Linux SLES12 / SLES_SAP12 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:4241-1 advisory.

    - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
    - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).
    - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).
    - CVE-2022-42311, CVE-2022-42312, CVE-2022-42313, CVE-2022-42314, CVE-2022-42315, CVE-2022-42316,     CVE-2022-42317, CVE-2022-42318: xen: Xenstore: Guests can let xenstored run out of memory (bsc#1204482)
    - CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)
    - CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)
    - CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)
    - CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)
    - CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)
    - CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes     (bsc#1204494)
    - CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitrary number of nodes via     transactions (bsc#1204496)
    - xen: Frontends vulnerable to backends (bsc#1193923)

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

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

The remote SUSE Linux SLES12 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:4051-1 advisory.

    - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
    - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).
    - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).
    - CVE-2022-42311, CVE-2022-42312, CVE-2022-42313, CVE-2022-42314, CVE-2022-42315, CVE-2022-42316,     CVE-2022-42317, CVE-2022-42318: xen: Xenstore: Guests can let xenstored run out of memory (bsc#1204482)
    - CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)
    - CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)
    - CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)
    - CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)
    - CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes     (bsc#1204494)

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

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

The remote SUSE Linux SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:3971-1 advisory.

    - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
    - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).
    - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).
    - CVE-2022-42311, CVE-2022-42312, CVE-2022-42313, CVE-2022-42314, CVE-2022-42315, CVE-2022-42316,     CVE-2022-42317, CVE-2022-42318: xen: Xenstore: Guests can let xenstored run out of memory (bsc#1204482)
    - CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)
    - CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)
    - CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)
    - CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)
    - CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)
    - CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes     (bsc#1204494)
    - CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitrary number of nodes via     transactions (bsc#1204496)
    - xen: Frontends vulnerable to backends (bsc#1193923).

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

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

The remote SUSE Linux SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:3928-1 advisory.

    - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
    - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).
    - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).
    - CVE-2022-42311, CVE-2022-42312, CVE-2022-42313, CVE-2022-42314, CVE-2022-42315, CVE-2022-42316,     CVE-2022-42317, CVE-2022-42318: xen: Xenstore: Guests can let xenstored run out of memory (bsc#1204482)
    - CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)
    - CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)
    - CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)
    - CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)
    - CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)
    - CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes     (bsc#1204494)
    - CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitray number of nodes via     transactions (bsc#1204496)
    - CVE-2022-26363,CVE-2022-26364: xen: Insufficient care with non-coherent mappings (bsc#1199966).
    - CVE-2022-26365,CVE-2022-33740,CVE-2022-33741,CVE-2022-33742: xen: Linux disk/nic frontends data leaks     (bsc#1200762).
    - xen: Frontends vulnerable to backends (bsc#1193923).

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

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

The remote SUSE Linux SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:3925-1 advisory.

    - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
    - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).
    - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).
    - CVE-2022-42311, CVE-2022-42312, CVE-2022-42313, CVE-2022-42314, CVE-2022-42315, CVE-2022-42316,     CVE-2022-42317, CVE-2022-42318: xen: Xenstore: Guests can let xenstored run out of memory (bsc#1204482)
    - CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)
    - CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)
    - CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)
    - CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)
    - CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)
    - CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes     (bsc#1204494)
    - CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitrary number of nodes via     transactions (bsc#1204496)
    - xen: Frontends vulnerable to backends (bsc#1193923)

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

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

The remote SUSE Linux SLES12 / SLES_SAP12 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:3728-1 advisory.

    - CVE-2022-26365: Fixed issue where Linux Block and Network PV device frontends don't zero memory regions     before sharing them with the backend (bsc#1200762).
      - CVE-2022-33740: Fixed issue where Linux Block and Network PV device frontends don't zero memory     regions before sharing them with the backend (bsc#1200762).
      - CVE-2022-33741: Fixed issue where data residing in the same 4K page as data shared with a backend was     being accessible by such backend (bsc#1200762).
      - CVE-2022-33742: Fixed issue where data residing in the same 4K page as data shared with a backend was     being accessible by such backend (bsc#1200762).
      - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
      - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).
      - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).

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

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

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2022:3665-1 advisory.

    - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).
      - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).
      - CVE-2022-26365: Fixed issue where Linux Block and Network PV device frontends don't zero memory     regions before sharing them with the backend (bsc#1200762).
      - CVE-2022-33740: Fixed issue where Linux Block and Network PV device frontends don't zero memory     regions before sharing them with the backend (bsc#1200762).
      - CVE-2022-33741: Fixed issue where data residing in the same 4K page as data shared with a backend was     being accessible by such backend (bsc#1200762).
      - CVE-2022-33742: Fixed issue where data residing in the same 4K page as data shared with a backend was     being accessible by such backend (bsc#1200762).
      - CVE-2022-33745: Fixed an insufficient TLB flush for x86 PV guests in shadow mode (bsc#1201394).
      - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).

      Bugfixes:

      - Fixed logic error in built-in default of max_event_channels (bsc#1167608, bsc#1201631).
      - Fixed issue where dom0 fails to boot with constrained vcpus and nodes (bsc#1197081).
      - Included upstream bugfixes (bsc#1027519).

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

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

This update for xen fixes the following issues :

Security issue fixed :

CVE-2021-28689: Fixed some x86 speculative vulnerabilities with bare (non-shim) 32-bit PV guests (XSA-370) (bsc#1185104)

Make sure xencommons is in a format as expected by fillup.
(bsc#1185682)

Each comment needs to be followed by an enabled key. Otherwise fillup will remove manually enabled key=value pairs, along with everything that looks like a stale comment, during next pkg update

A recent systemd update caused a regression in xenstored.service systemd now fails to track units that use systemd-notify (bsc#1183790)

Added a delay between the call to systemd-notify and the final exit of the wrapper script (bsc#1185021, bsc#1185196)

Note that Tenable Network Security has extracted the preceding description block directly from the SUSE security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

ID	Name	Product	Family	Severity
232305	Linux Distros Unpatched Vulnerability : CVE-2021-28689	Nessus	Misc.	medium
168242	SUSE SLES12: xen / xen-doc-html / xen-libs / xen-libs-32bit / xen-tools / etc (SUSE-SU-2022:4241-1)	Nessus	SuSE Local Security Checks	high
167932	SUSE SLES12: xen / xen-doc-html / xen-libs / xen-libs-32bit / xen-tools / etc (SUSE-SU-2022:4051-1)	Nessus	SuSE Local Security Checks	high
167515	SUSE SLES15: xen / xen-devel / xen-libs / xen-tools / xen-tools-domU / etc (SUSE-SU-2022:3971-1)	Nessus	SuSE Local Security Checks	high
167337	SUSE SLES15 Security Update : xen (SUSE-SU-2022:3928-1)	Nessus	SuSE Local Security Checks	high
167242	SUSE SLES15 Security Update : xen (SUSE-SU-2022:3925-1)	Nessus	SuSE Local Security Checks	high
166529	SUSE SLES12: xen / xen-devel / xen-doc-html / xen-libs / xen-libs-32bit / etc (SUSE-SU-2022:3728-1)	Nessus	SuSE Local Security Checks	high
166301	SUSE SLED15: xen / xen-devel / xen-doc-html / xen-libs / xen-libs-32bit / etc (SUSE-SU-2022:3665-1)	Nessus	SuSE Local Security Checks	high
149801	SUSE SLES12 Security Update : xen (SUSE-SU-2021:1648-1)	Nessus	SuSE Local Security Checks	medium

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