CVE-2026-0665: Red Hat Enterprise Linux 10 · Out-of-bounds Write
Affects Red Hat Enterprise Linux 10Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 18 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red HatRed Hat Enterprise Linux 10 | Affected– | Fixed in– |
| Red HatRed Hat Enterprise Linux 6 | Affected– | Fixed in– |
| Red HatRed Hat Enterprise Linux 7 | Affected– | Fixed in– |
| Red HatRed Hat Enterprise Linux 8 | Affected– | Fixed in– |
| Red HatRed Hat Enterprise Linux 9 | Affected– | Fixed in– |
| Red HatRed Hat OpenShift Container Platform 4 | Affected– | Fixed in– |
AI-suggested
1. Upgrade QEMU: Apply patches or upgrade to a QEMU version beyond 8.0.0 that addresses CVE-2026-0665 as soon as they become available from trusted sources. 2. Restrict Guest Privileges: Limit the privileges of guest VMs to minimize the ability to invoke hypercalls that could trigger the vulnerability. 3. Harden Hypercall Interfaces: Implement monitoring and filtering of Xen physdev hypercalls to detect and block anomalous or suspicious calls from guests. 4. Isolate Critical Hosts: Use strict network and access controls to isolate hosts running vulnerable QEMU instances, reducing exposure to potentially malicious guests. 5. Monitor Host Stability: Deploy host-level monitoring to detect crashes or unusual behavior in QEMU processes that may indicate exploitation attempts. 6. Employ Security Best Practices: Use SELinux/AppArmor profiles or similar sandboxing techniques to limit the impact of compromised QEMU processes. 7. Incident Response Preparedness: Prepare response plans for potential denial of service incidents affecting virtualization hosts. 8. Vendor Coordination: Engage with QEMU maintainers and Linux distribution vendors for timely updates and advisories.
Description
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.