Vulnerability Description
An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Xen | Xen | <= 4.14.1 |
| Linux | Linux Kernel | >= 4.1.44, < 4.2 |
| Netapp | Hci Compute Node Bios | - |
| Netapp | Hci Compute Node | - |
| Netapp | Solidfire \& Hci Management Node | - |
| Netapp | Solidfire \& Hci Storage Node | - |
| Debian | Debian Linux | 9.0 |
Related Weaknesses (CWE)
References
- https://lists.debian.org/debian-lts-announce/2021/02/msg00018.htmlMailing ListThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00010.htmlMailing ListThird Party Advisory
- https://security.gentoo.org/glsa/202107-30Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210205-0001/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4843Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-350.htmlPatchVendor Advisory
- https://lists.debian.org/debian-lts-announce/2021/02/msg00018.htmlMailing ListThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00010.htmlMailing ListThird Party Advisory
- https://security.gentoo.org/glsa/202107-30Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210205-0001/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4843Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-350.htmlPatchVendor Advisory
FAQ
What is CVE-2020-29569?
CVE-2020-29569 is a vulnerability with a CVSS score of 8.8 (HIGH). An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when sto...
How severe is CVE-2020-29569?
CVE-2020-29569 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2020-29569?
Check the references section above for vendor advisories and patch information. Affected products include: Xen Xen, Linux Linux Kernel, Netapp Hci Compute Node Bios, Netapp Hci Compute Node, Netapp Solidfire \& Hci Management Node.