CVE-2026-0665
published 2026-02-18CVE-2026-0665: An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process…
PriorityP426medium6.5CVSS 3.1
AVLACLPRLUINSCCNINAH
EPSS
0.14%
4.0th percentile
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
Affected
6 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | qemu | < qemu 1:10.2.0+ds-2 (forky) | qemu 1:10.2.0+ds-2 (forky) |
| qemu | qemu | >= 0 < 1:10.0.8+ds-0+deb13u1 | 1:10.0.8+ds-0+deb13u1 |
| qemu | qemu | >= 0 < 1:10.2.0+ds-2 | 1:10.2.0+ds-2 |
| qemu | qemu | >= 0 < 1:6.2+dfsg-2ubuntu6.28 | 1:6.2+dfsg-2ubuntu6.28 |
| qemu | qemu | >= 0 < 1:8.2.2+ds-0ubuntu1.13 | 1:8.2.2+ds-0ubuntu1.13 |
| qemu | qemu | >= 0 < 1:10.1.0+ds-5ubuntu2.4 | 1:10.1.0+ds-5ubuntu2.4 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
osv6.5MEDIUM
vendor_debian6.5LOW
vendor_redhat6.5MEDIUM
vendor_ubuntu5.5MEDIUM
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OSV
qemu vulnerabilities
osv·2026-03-04·CVSS 5.5
CVE-2024-8354 [MEDIUM] qemu vulnerabilities
qemu vulnerabilities
It was discovered that the UHCI controller implementation of QEMU could be
brought into an invalid state. An attacker inside the guest could possibly
use this issue to cause QEMU to crash, resulting in a denial of service.
(CVE-2024-8354)
It was discovered that QEMU incorrectly handled memory during certain VNC
operations. An remote attacker could possibly use this issue to cause QEMU
to crash, resulting in a denial of service, or possibly execute arbitrary
code. (CVE-2025-11234)
It was discovered that the e1000 network device implementation of QEMU
could be made to write out of bounds. An attacker inside the guest could
possibly use this issue to cause QEMU to crash, resulting in a denial of
service, or possibly execute arbitrary code. This issue only affected
Ubun
GHSA
GHSA-4pq4-6gr5-cr69: An off-by-one error was found in QEMU's KVM Xen guest support
ghsa_unreviewed·2026-02-18
CVE-2026-0665 [MEDIUM] CWE-787 GHSA-4pq4-6gr5-cr69: An off-by-one error was found in QEMU's KVM Xen guest support
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
OSV
CVE-2026-0665: An off-by-one error was found in QEMU's KVM Xen guest support
osv·2026-02-18·CVSS 6.5
CVE-2026-0665 [MEDIUM] CVE-2026-0665: An off-by-one error was found in QEMU's KVM Xen guest support
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
Ubuntu
QEMU vulnerabilities
vendor_ubuntu·2026-03-04·CVSS 5.5
CVE-2026-0665 [MEDIUM] QEMU vulnerabilities
Title: QEMU vulnerabilities
Summary: Several security issues were fixed in QEMU.
It was discovered that the UHCI controller implementation of QEMU could be
brought into an invalid state. An attacker inside the guest could possibly
use this issue to cause QEMU to crash, resulting in a denial of service.
(CVE-2024-8354)
It was discovered that QEMU incorrectly handled memory during certain VNC
operations. An remote attacker could possibly use this issue to cause QEMU
to crash, resulting in a denial of service, or possibly execute arbitrary
code. (CVE-2025-11234)
It was discovered that the e1000 network device implementation of QEMU
could be made to write out of bounds. An attacker inside the guest could
possibly use this issue to cause QEMU to crash, resulting in a denial of
service, or p
Red Hat
qemu-kvm: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq
vendor_redhat·2026-01-09·CVSS 6.5
CVE-2026-0665 [MEDIUM] CWE-787 qemu-kvm: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq
qemu-kvm: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
Statement: Xen guest support is disabled at build time in the `qemu-kvm` packages as shipped with Red Hat Enterprise Linux. Consequently, RHEL is not affected by this CVE.
Package: qemu-kvm (Red
Debian
CVE-2026-0665: qemu - An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest...
vendor_debian·2026·CVSS 6.5
CVE-2026-0665 [MEDIUM] CVE-2026-0665: qemu - An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest...
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved (fixed in 1:10.2.0+ds-2)
sid: resolved (fixed in 1:10.2.0+ds-2)
trixie: resolved (fixed in 1:10.0.8+ds-0+deb13u1)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-0665 qemu: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq [fedora-42]
bugzilla·2026-01-12·CVSS 6.5
CVE-2026-0665 [MEDIUM] CVE-2026-0665 qemu: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq [fedora-42]
CVE-2026-0665 qemu: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq [fedora-42]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Discussion:
This message is a reminder that Fedora Linux 42 is nearing its end of life.
Fedora will stop maintaining and issuing updates for Fedora Linux 42 on 2026-05-13.
It is Fedora's policy to close all bug reports fr
Wiz
CVE-2026-0665 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 6.5
CVE-2026-0665 [MEDIUM] CVE-2026-0665 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-0665 :
Wolfi vulnerability analysis and mitigation
An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.
Source : NVD
## 6.5
Score
Published February 18, 2026
Severity MEDIUM
CNA Score 6.5
Affected Technologies
Wolfi
Chainguard
Has Public Exploit No
Has CISA KEV Exploit No
CISA KEV Release Date N/A
CISA KEV Due Date N/A
Exploitation Probability Percentile (EPSS) 0.7
Exploitation Probability (EPSS) N/A
Affected packages and libraries
qemu-linux-user
qemu-ppc
Sources
NVD
Chainguard No Fix Added at: Feb 19, 2026
Debian 13, 14 Severity MEDIU
2026-02-18
Published