CVE-2021-3416

Severity: medium (CVSS 6.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-18 · updated 2026-06-17
Weakness: CWE-835

Description

A potential stack overflow via infinite loop issue was found in various NIC emulators of QEMU in versions up to and including 5.2.0. The issue occurs in loopback mode of a NIC wherein reentrant DMA checks get bypassed. A guest user/process may use this flaw to consume CPU cycles or crash the QEMU process on the host resulting in DoS scenario.

Affected products

Debian Linux: 9.0, 10.0
Fedoraproject Fedora: 33
QEMU: through 5.2.0
Red Hat Enterprise Linux: 6.0, 7.0, 8.0

References

https://bugzilla.redhat.com/show_bug.cgi?id=1932827
https://lists.debian.org/debian-lts-announce/2021/04/msg00009.html
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
https://security.gentoo.org/glsa/202208-27
https://security.netapp.com/advisory/ntap-20210507-0002/
https://www.openwall.com/lists/oss-security/2021/02/26/1
https://bugzilla.redhat.com/show_bug.cgi?id=1932827
https://lists.debian.org/debian-lts-announce/2021/04/msg00009.html
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
https://security.gentoo.org/glsa/202208-27
https://security.netapp.com/advisory/ntap-20210507-0002/
https://www.openwall.com/lists/oss-security/2021/02/26/1

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