CVE-2015-6855

CVE-2015-6855 is a high-severity vulnerability in Qemu with a CVSS 3.x base score of 7.5. 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-369.

Key facts

• Severity: High (CVSS 3.x base score 7.5)
• CVSS v2: 5.0
• EPSS exploit prediction: 4% (88th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-369
• Affected product: Qemu
• Published: 2015-11-06
• Last modified: 2026-06-17

Description

hw/ide/core.c in QEMU does not properly restrict the commands accepted by an ATAPI device, which allows guest users to cause a denial of service or possibly have unspecified other impact via certain IDE commands, as demonstrated by a WIN_READ_NATIVE_MAX command to an empty drive, which triggers a divide-by-zero error and instance crash.

Frequently asked questions

What is CVE-2015-6855?

hw/ide/core.c in QEMU does not properly restrict the commands accepted by an ATAPI device, which allows guest users to cause a denial of service or possibly have unspecified other impact via certain IDE commands, as demonstrated by a WIN_READ_NATIVE_MAX command to an empty drive, which triggers a divide-by-zero error and instance crash.

How severe is CVE-2015-6855?

CVE-2015-6855 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2015-6855 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2015-6855?

CVE-2015-6855 primarily affects Qemu. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2015-6855?

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-2015-6855 published?

CVE-2015-6855 was published on 2015-11-06 and last updated on 2026-06-17.

References

• http://lists.fedoraproject.org/pipermail/package-announce/2015-October/168602.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-October/169036.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-October/169039.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-October/169327.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-October/169341.html
• http://lists.fedoraproject.org/pipermail/package-announce/2015-September/167369.html
• http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00019.html
• http://www.debian.org/security/2015/dsa-3361
• http://www.debian.org/security/2015/dsa-3362
• http://www.openwall.com/lists/oss-security/2015/09/10/1
• http://www.openwall.com/lists/oss-security/2015/09/10/2
• http://www.securityfocus.com/bid/76691
• http://www.ubuntu.com/usn/USN-2745-1
• https://lists.gnu.org/archive/html/qemu-devel/2015-09/msg02479.html
• https://security.gentoo.org/glsa/201602-01
• https://www.arista.com/en/support/advisories-notices/security-advisories/1188-security-advisory-14

Affected products (13)

• cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
• cpe:2.3:o:fedoraproject:fedora:21:*:*:*:*:*:*:*
• cpe:2.3:o:fedoraproject:fedora:22:*:*:*:*:*:*:*
• cpe:2.3:o:fedoraproject:fedora:23:*:*:*:*:*:*:*
• cpe:2.3:o:suse:linux_enterprise_desktop:12:-:*:*:*:*:*:*
• cpe:2.3:o:suse:linux_enterprise_server:12:-:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:15.04:*:*:*:*:*:*:*
• cpe:2.3:o:arista:eos:-:*:*:*:*:*:*:*

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