CVE-2017-7539

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 5.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-07-26 · updated 2026-06-17
Weakness: CWE-617

Description

An assertion-failure flaw was found in Qemu before 2.10.1, in the Network Block Device (NBD) server's initial connection negotiation, where the I/O coroutine was undefined. This could crash the qemu-nbd server if a client sent unexpected data during connection negotiation. A remote user or process could use this flaw to crash the qemu-nbd server resulting in denial of service.

Affected products

QEMU: before 2.10.1 — fixed in 2.10.1
OpenStack: 6.0, 7.0, 8, 9, 10, 11
RedHat Virtualization: 4.0, 3.0

How to fix

Upgrade to a fixed version: QEMU 2.10.1. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2017/07/21/4
http://www.securityfocus.com/bid/99944
https://access.redhat.com/errata/RHSA-2017:2628
https://access.redhat.com/errata/RHSA-2017:3466
https://access.redhat.com/errata/RHSA-2017:3470
https://access.redhat.com/errata/RHSA-2017:3471
https://access.redhat.com/errata/RHSA-2017:3472
https://access.redhat.com/errata/RHSA-2017:3473
https://access.redhat.com/errata/RHSA-2017:3474
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-7539
https://git.qemu.org/?p=qemu.git%3Ba=commitdiff%3Bh=2b0bbc4f8809c972bad134bc1a2570dbb01dea0b
https://git.qemu.org/?p=qemu.git%3Ba=commitdiff%3Bh=ff82911cd3f69f028f2537825c9720ff78bc3f19

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