CVE-2018-11806

CVE-2018-11806 is a high-severity vulnerability in Qemu with a CVSS 3.x base score of 8.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

• Severity: High (CVSS 3.x base score 8.2)
• CVSS v2: 7.2
• EPSS exploit prediction: 1% (53rd percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-787
• Affected product: Qemu
• Published: 2018-06-13
• Last modified: 2026-06-17

Description

m_cat in slirp/mbuf.c in Qemu has a heap-based buffer overflow via incoming fragmented datagrams.

Frequently asked questions

What is CVE-2018-11806?

m_cat in slirp/mbuf.c in Qemu has a heap-based buffer overflow via incoming fragmented datagrams.

How severe is CVE-2018-11806?

CVE-2018-11806 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-11806 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-11806?

CVE-2018-11806 primarily affects Qemu. In total, 26 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-11806?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-11806 published?

CVE-2018-11806 was published on 2018-06-13 and last updated on 2026-06-17.

References

• http://www.openwall.com/lists/oss-security/2018/06/07/1
• http://www.securityfocus.com/bid/104400
• https://access.redhat.com/errata/RHSA-2018:2462
• https://access.redhat.com/errata/RHSA-2018:2762
• https://access.redhat.com/errata/RHSA-2018:2822
• https://access.redhat.com/errata/RHSA-2018:2887
• https://access.redhat.com/errata/RHSA-2019:2892
• https://bugzilla.redhat.com/show_bug.cgi?id=1586245
• https://lists.debian.org/debian-lts-announce/2019/05/msg00010.html
• https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg01012.html
• https://seclists.org/bugtraq/2019/May/76
• https://usn.ubuntu.com/3826-1/
• https://www.debian.org/security/2019/dsa-4454
• https://www.zerodayinitiative.com/advisories/ZDI-18-567/

Affected products (26)

• cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
• cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:*
• cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:*
• cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:*
• cpe:2.3:a:redhat:openstack:12:*:*:*:*:*:*:*
• cpe:2.3:a:redhat:openstack:13:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:7.5:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:7.6:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_eus:7.7:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_aus:7.7:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_server_tus:7.7:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
• cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
• cpe:2.3:a:redhat:virtualization:4.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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