CVE-2022-42332
What it is
x86 shadow plus log-dirty mode use-after-free In environments where host assisted address translation is necessary but Hardware Assisted Paging (HAP) is unavailable, Xen will run guests in so called shadow mode. Shadow mode maintains a pool of memory used for both shadow page tables as well as auxiliary data structures. To migrate or snapshot guests, Xen additionally runs them in so called log-dirty mode. The data structures needed by the log-dirty tracking are part of aformentioned auxiliary data. In order to keep error handling efforts within reasonable bounds, for operations which may require memory allocations shadow mode logic ensures up front that enough memory is available for the worst case requirements. Unfortunately, while page table memory is properly accounted for on the code path requiring the potential establishing of new shadows, demands by the log-dirty infrastructure were not taken into consideration. As a result, just established shadow page tables could be freed again immediately, while other code is still accessing them on the assumption that they would remain allocated.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Xen
- Debian Linux 11.0
- Fedoraproject Fedora 37
- Fedoraproject Fedora 38
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-42332.md and follow it. Check whether this project is affected by CVE-2022-42332. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- http://xenbits.xen.org/xsa/advisory-427.html
- https://xenbits.xenproject.org/xsa/advisory-427.txt
- http://xenbits.xen.org/xsa/advisory-427.html
- https://xenbits.xenproject.org/xsa/advisory-427.txt
References
- http://www.openwall.com/lists/oss-security/2023/03/21/1
- http://xenbits.xen.org/xsa/advisory-427.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5L6PM4RE7MUE6OWA32ZVOXCP235RM2TM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/APBMS2Q6746AXAFAITNJMGBNFGNMVLWR/
- https://security.gentoo.org/glsa/202402-07
- https://www.debian.org/security/2023/dsa-5378
- https://xenbits.xenproject.org/xsa/advisory-427.txt
- http://www.openwall.com/lists/oss-security/2023/03/21/1
- http://xenbits.xen.org/xsa/advisory-427.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5L6PM4RE7MUE6OWA32ZVOXCP235RM2TM/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/APBMS2Q6746AXAFAITNJMGBNFGNMVLWR/
- https://security.gentoo.org/glsa/202402-07
- https://www.debian.org/security/2023/dsa-5378
- https://xenbits.xenproject.org/xsa/advisory-427.txt