CVE-2021-28687
published 2021-06-11CVE-2021-28687: HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of afterwards…
PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.31%
23.7th percentile
HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of afterwards by calling a specific set of functions. Many internal data structures also require this initialize / dispose discipline, but not all of them. When the "soft reset" feature was implemented, the libxl__domain_suspend_state structure didn't require any initialization or disposal. At some point later, an initialization function was introduced for the structure; but the "soft reset" path wasn't refactored to call the initialization function. When a guest nwo initiates a "soft reboot", uninitialized data structure leads to an assert() when later code finds the structure in an unexpected state. The effect of this is to crash the process monitoring the guest. How this affects the system depends on the structure of the toolstack. For xl, this will have no security-relevant effect: every VM has its own independent monitoring process, which contains no state. The domain in question will hang in a crashed state, but can be destroyed by `xl destroy` just like any other non-cooperating domain. For daemon-based toolstacks linked against libxl, such as libvirt, this will crash the toolstack, losing the state of any in-progress operations (localized DoS), and preventing further administrator operations unless the daemon is configured to restart automatically (system-wide DoS). If crashes "leak" resources, then repeated crashes could use up resources, also causing a system-wide DoS.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | xen | < xen 4.14.2+25-gb6a8c4f72d-1 (bookworm) | xen 4.14.2+25-gb6a8c4f72d-1 (bookworm) |
| xen | xen | — | — |
| xen | xen | — | — |
| xen | xen | — | — |
| xen | xen | >= 0 < 4.14.2+25-gb6a8c4f72d-1 | 4.14.2+25-gb6a8c4f72d-1 |
| xen | xen | >= 0 < 4.14.2+25-gb6a8c4f72d-1 | 4.14.2+25-gb6a8c4f72d-1 |
| xen | xen | >= 0 < 4.14.2+25-gb6a8c4f72d-1 | 4.14.2+25-gb6a8c4f72d-1 |
| xen | xen | >= 0 < 4.14.2+25-gb6a8c4f72d-1 | 4.14.2+25-gb6a8c4f72d-1 |
| xen | xen | 4.12 – 4.15.0 | — |
| xen | xen | >= 4.12.x < unspecified | unspecified |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvdv2.04.9MEDIUMAV:L/AC:L/Au:N/C:N/I:N/A:C
osv5.5MEDIUM
vendor_debian5.5MEDIUM
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GHSA
GHSA-f8g3-gxq4-xqv7: HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of af
ghsa_unreviewed·2022-05-24
CVE-2021-28687 [MEDIUM] CWE-909 GHSA-f8g3-gxq4-xqv7: HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of af
HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of afterwards by calling a specific set of functions. Many internal data structures also require this initialize / dispose discipline, but not all of them. When the "soft reset" feature was implemented, the libxl__domain_suspend_state structure didn't require any initialization or disposal. At some point later, an initialization function was introduced for the structure; but the "soft reset" path wasn't refactored to call the initialization function. When a guest nwo initiates a "soft reboot", uninitialized data structure leads to an assert() when later code finds the structure in an unexpected state. The effect of this is to crash the process mon
OSV
CVE-2021-28687: HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of af
osv·2021-06-11·CVSS 5.5
CVE-2021-28687 [MEDIUM] CVE-2021-28687: HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of af
HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of afterwards by calling a specific set of functions. Many internal data structures also require this initialize / dispose discipline, but not all of them. When the "soft reset" feature was implemented, the libxl__domain_suspend_state structure didn't require any initialization or disposal. At some point later, an initialization function was introduced for the structure; but the "soft reset" path wasn't refactored to call the initialization function. When a guest nwo initiates a "soft reboot", uninitialized data structure leads to an assert() when later code finds the structure in an unexpected state. The effect of this is to crash the process mon
Debian
CVE-2021-28687: xen - HVM soft-reset crashes toolstack libxl requires all data structures passed acros...
vendor_debian·2021·CVSS 5.5
CVE-2021-28687 [MEDIUM] CVE-2021-28687: xen - HVM soft-reset crashes toolstack libxl requires all data structures passed acros...
HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of afterwards by calling a specific set of functions. Many internal data structures also require this initialize / dispose discipline, but not all of them. When the "soft reset" feature was implemented, the libxl__domain_suspend_state structure didn't require any initialization or disposal. At some point later, an initialization function was introduced for the structure; but the "soft reset" path wasn't refactored to call the initialization function. When a guest nwo initiates a "soft reboot", uninitialized data structure leads to an assert() when later code finds the structure in an unexpected state. The effect of this is to crash the process mon
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-06-11
Published