Vulnerability Description
A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB packets are combined into a single, large transfer request, to reduce the overhead and improve performance. The combined size of the bulk transfer is used to dynamically allocate a variable length array (VLA) on the stack without proper validation. Since the total size is not bounded, a malicious guest could use this flaw to influence the array length and cause the QEMU process to perform an excessive allocation on the stack, resulting in a denial of service.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Qemu | Qemu | <= 6.0.0 |
| Redhat | Enterprise Linux | 8.0 |
| Debian | Debian Linux | 9.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1955695Issue TrackingPatchThird Party Advisory
- https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fPatchThird Party Advisory
- https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5fPatchThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/09/msg00000.htmlMailing ListThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing ListThird Party Advisory
- https://security.gentoo.org/glsa/202208-27Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210708-0008/Third Party Advisory
- https://www.openwall.com/lists/oss-security/2021/05/05/5Mailing ListPatchThird Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1955695Issue TrackingPatchThird Party Advisory
- https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fPatchThird Party Advisory
- https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5fPatchThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/09/msg00000.htmlMailing ListThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing ListThird Party Advisory
- https://security.gentoo.org/glsa/202208-27Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210708-0008/Third Party Advisory
FAQ
What is CVE-2021-3527?
CVE-2021-3527 is a vulnerability with a CVSS score of 5.5 (MEDIUM). A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB packets are combined into a single, large transfer request, to reduce the overhead and improve performance. The combined si...
How severe is CVE-2021-3527?
CVE-2021-3527 has been rated MEDIUM with a CVSS base score of 5.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-3527?
Check the references section above for vendor advisories and patch information. Affected products include: Qemu Qemu, Redhat Enterprise Linux, Debian Debian Linux.