Uncontrolled Recursion Affecting xen package, versions <4.14.1-r0
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Test your applications- Snyk ID SNYK-ALPINE320-XEN-7012516
- published 23 May 2024
- disclosed 15 Dec 2020
Introduced: 15 Dec 2020
CVE-2020-29566 Open this link in a new tabHow to fix?
Upgrade Alpine:3.20
xen
to version 4.14.1-r0 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream xen
package and not the xen
package as distributed by Alpine
.
See How to fix?
for Alpine:3.20
relevant fixed versions and status.
An issue was discovered in Xen through 4.14.x. When they require assistance from the device model, x86 HVM guests must be temporarily de-scheduled. The device model will signal Xen when it has completed its operation, via an event channel, so that the relevant vCPU is rescheduled. If the device model were to signal Xen without having actually completed the operation, the de-schedule / re-schedule cycle would repeat. If, in addition, Xen is resignalled very quickly, the re-schedule may occur before the de-schedule was fully complete, triggering a shortcut. This potentially repeating process uses ordinary recursive function calls, and thus could result in a stack overflow. A malicious or buggy stubdomain serving a HVM guest can cause Xen to crash, resulting in a Denial of Service (DoS) to the entire host. Only x86 systems are affected. Arm systems are not affected. Only x86 stubdomains serving HVM guests can exploit the vulnerability.
References
- https://www.debian.org/security/2020/dsa-4812
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI/
- https://xenbits.xenproject.org/xsa/advisory-348.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI/
- https://security.gentoo.org/glsa/202107-30