{"id":"CVE-2021-28689","aliases":["DEBIAN-CVE-2021-28689","EUVD-2021-15346","GHSA-45vh-fhgx-cr2p","SUSE-SU-2021:1648-1","SUSE-SU-2022:3665-1","SUSE-SU-2022:3728-1","SUSE-SU-2022:3925-1","SUSE-SU-2022:3928-1","SUSE-SU-2022:3971-1","SUSE-SU-2022:4051-1","SUSE-SU-2022:4241-1","UBUNTU-CVE-2021-28689"],"status":"published","title":"x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest...","description":"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.","severity":{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.0036,"percentile":0.30095,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-119","CWE-212"],"published":"2021-05-19T12:00:08Z","modified":"2026-10-17T12:56:15Z","fixes":[{"ecosystem":"SUSE:OpenStack Cloud 9","package":"xen","fixed_in":["4.11.4_18-2.54.1"],"sources":["osv"]},{"ecosystem":"SUSE:OpenStack Cloud Crowbar 9","package":"xen","fixed_in":["4.11.4_18-2.54.1"],"sources":["osv"]},{"ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 12 SP4","package":"xen","fixed_in":["4.11.4_18-2.54.1"],"sources":["osv"]},{"ecosystem":"SUSE:Linux Enterprise Server 12 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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.","status":"published","published":"2021-06-11T14:53:06Z","modified":"2024-08-03T21:47:33.181Z","updated_at":"2026-11-02T14:33:09.175141Z"}],"euvd":[{"id":"EUVD-2021-15346","description":"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.","status":"published","published":"2021-06-11T14:53:06Z","modified":"2024-08-03T21:47:33Z","updated_at":"2026-11-03T03:24:46.117926Z"}],"ghsa":[{"id":"GHSA-45vh-fhgx-cr2p","title":"x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest...","description":"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.","status":"published","published":"2022-05-24T19:05:06Z","modified":"2023-08-17T05:02:00Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-119"],"updated_at":"2026-11-02T14:54:45.82233Z"}],"nvd":[{"id":"CVE-2021-28689","description":"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.","status":"published","published":"2021-06-11T15:15:11.187Z","modified":"2026-06-17T03:46:48.053Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":2.1,"vector":"AV:L/AC:L/Au:N/C:P/I:N/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-212"],"updated_at":"2026-11-02T14:06:54.439974Z"}],"osv":[{"id":"CVE-2021-28689","description":"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.","status":"published","published":"2021-06-11T15:15:11.187Z","modified":"2026-03-14T10:53:39.280146Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:19.129331Z"},{"id":"DEBIAN-CVE-2021-28689","description":"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.","status":"published","published":"2021-06-11T15:15:11.187Z","modified":"2026-09-01T20:04:26.901604094Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:34.94143Z"},{"id":"UBUNTU-CVE-2021-28689","description":"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.","status":"published","published":"2021-06-11T15:15:00Z","modified":"2026-10-17T12:56:15.037403794Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:54:26.779273Z"},{"id":"SUSE-SU-2021:1648-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\nSecurity issue fixed:\n\n- CVE-2021-28689: Fixed some x86 speculative vulnerabilities with bare (non-shim) 32-bit PV guests (XSA-370) (bsc#1185104)\n\n- Make sure xencommons is in a format as expected by fillup. (bsc#1185682)\n\n  Each comment needs to be followed by an enabled key. Otherwise\n  fillup will remove manually enabled key=value pairs, along with\n  everything that looks like a stale comment, during next pkg update\n\n- A recent systemd update caused a regression in xenstored.service\n  systemd now fails to track units that use systemd-notify (bsc#1183790)\n- Added a delay between the call to systemd-notify and the final exit\n  of the wrapper script (bsc#1185021, bsc#1185196)\n","status":"published","published":"2021-05-19T12:00:08Z","modified":"2025-05-02T04:31:20.229791Z","updated_at":"2026-11-02T15:53:49.138643Z"},{"id":"SUSE-SU-2022:3665-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n                                                                                                                                                                          \n  - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).                                                                                     \n  - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).\n  - 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).\n  - 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).\n  - 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).\n  - 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).\n  - CVE-2022-33745: Fixed an insufficient TLB flush for x86 PV guests in shadow mode (bsc#1201394).\n  - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n\n  Bugfixes:                                                                                                                                                               \n                                                                                                                                                                          \n  - Fixed logic error in built-in default of max_event_channels (bsc#1167608, bsc#1201631). \n  - Fixed issue where dom0 fails to boot with constrained vcpus and nodes (bsc#1197081).\n  - Included upstream bugfixes (bsc#1027519).\n","status":"published","published":"2022-10-19T18:29:23Z","modified":"2026-02-04T03:26:38.780658Z","updated_at":"2026-11-02T15:53:51.440565Z"},{"id":"SUSE-SU-2022:3728-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n  - 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).\n  - 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).\n  - 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).\n  - 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).\n  - CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).\n  - CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n  - CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).\n\n","status":"published","published":"2022-10-25T13:40:54Z","modified":"2026-02-04T03:17:01.086196Z","updated_at":"2026-11-02T15:53:51.440565Z"},{"id":"SUSE-SU-2022:3925-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).\n- CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).\n- CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n- 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)\n- CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)\n- CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)\n- CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)\n- CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)\n- CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)\n- CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes (bsc#1204494)\n- CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitrary number of nodes via transactions (bsc#1204496)\n- xen: Frontends vulnerable to backends (bsc#1193923)\n","status":"published","published":"2022-11-09T12:55:45Z","modified":"2026-02-04T03:51:15.371998Z","updated_at":"2026-11-02T15:53:51.440565Z"},{"id":"SUSE-SU-2022:3928-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).\n- CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).\n- CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n- 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)\n- CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)\n- CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)\n- CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)\n- CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)\n- CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)\n- CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes (bsc#1204494)\n- CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitray number of nodes via transactions (bsc#1204496)\n- CVE-2022-26363,CVE-2022-26364: xen: Insufficient care with non-coherent mappings (bsc#1199966).\n- CVE-2022-26365,CVE-2022-33740,CVE-2022-33741,CVE-2022-33742: xen: Linux disk/nic frontends data leaks (bsc#1200762).\n- xen: Frontends vulnerable to backends (bsc#1193923).\n","status":"published","published":"2022-11-10T08:28:50Z","modified":"2026-02-04T03:13:31.439214Z","updated_at":"2026-11-02T15:53:51.440565Z"},{"id":"SUSE-SU-2022:3971-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).\n- CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).\n- CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n- 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)\n- CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)\n- CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)\n- CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)\n- CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)\n- CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)\n- CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes (bsc#1204494)\n- CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitrary number of nodes via transactions (bsc#1204496)\n- xen: Frontends vulnerable to backends (bsc#1193923).\n","status":"published","published":"2022-11-14T13:24:42Z","modified":"2025-05-02T04:31:20.541384Z","updated_at":"2026-11-02T15:53:51.440565Z"},{"id":"SUSE-SU-2022:4051-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).                                                                                     \n- CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).                                                                                                       \n- CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n- 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)\n- CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)\n- CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)\n- CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)\n- CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)\n- CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes (bsc#1204494)\n","status":"published","published":"2022-11-17T14:24:03Z","modified":"2026-02-04T02:47:28.368251Z","updated_at":"2026-11-02T15:53:51.440565Z"},{"id":"SUSE-SU-2022:4241-1","title":"Security update for xen","description":"This update for xen fixes the following issues:\n\n- CVE-2022-33746: Fixed DoS due to excessively long P2M pool freeing (bsc#1203806).\n- CVE-2022-33748: Fixed DoS due to race in locking (bsc#1203807).\n- CVE-2021-28689: Fixed speculative vulnerabilities with bare (non-shim) 32-bit PV guests (bsc#1185104).\n- 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)\n- CVE-2022-42309: xen: Xenstore: Guests can crash xenstored (bsc#1204485)\n- CVE-2022-42310: xen: Xenstore: Guests can create orphaned Xenstore nodes (bsc#1204487)\n- CVE-2022-42319: xen: Xenstore: Guests can cause Xenstore to not free temporary memory (bsc#1204488)\n- CVE-2022-42320: xen: Xenstore: Guests can get access to Xenstore nodes of deleted domains (bsc#1204489)\n- CVE-2022-42321: xen: Xenstore: Guests can crash xenstored via exhausting the stack (bsc#1204490)\n- CVE-2022-42322,CVE-2022-42323: xen: Xenstore: cooperating guests can create arbitrary numbers of nodes (bsc#1204494)\n- CVE-2022-42325,CVE-2022-42326: xen: Xenstore: Guests can create arbitrary number of nodes via transactions (bsc#1204496)\n- xen: Frontends vulnerable to backends (bsc#1193923)\n","status":"published","published":"2022-11-28T08:22:20Z","modified":"2026-02-04T02:35:50.779304Z","updated_at":"2026-11-02T15:53:51.440565Z"}]}}