CVE-2018-18438

Qemu has integer overflows because IOReadHandler and its associated functions use a signed integer data type for a size value.

Published: 2018-10-19 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-18438 is rated Low Risk (34.6/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.44%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-18438

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.06% 0.44% +0.38%
2 2023-10-13 0.04% 0.06% +0.02%
3 2023-03-07 — 0.04% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-18438

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.0 MEDIUM
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]
2.1 2.0 LOW
AV:L/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 3.9 2.9 [email protected]

Weakness enumeration for CVE-2018-18438

OS Trackers for CVE-2018-18438

vendor priority summary link
debian not yet assigned CVE-2018-18438 not yet assigned priority: Debian including 1 source packages (qemu), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2018-18438
redhat — — https://access.redhat.com/security/cve/CVE-2018-18438
suse medium CVE-2018-18438 severity moderate: SUSE including 44 source package names (kvm-1.4.2-53.26.2, kvm-1.4.2-60.18.2, …), 139 product×package rows across 37 product lines (SLES for SAP Applications 11 SP3, SUSE CaaS Platform 4.5, … (37 product lines)): Known Not Affected 85, Fixed 54. https://www.suse.com/security/cve/CVE-2018-18438/
ubuntu low CVE-2018-18438 low priority: Ubuntu including 2 source packages (qemu, qemu-kvm), 16 status rows across 8 suites (bionic, cosmic, disco, eoan, focal, trusty, upstream, xenial): DNE 7, not-affected 5, ignored 2, needs-triage 2. https://ubuntu.com/security/CVE-2018-18438

Affected software / configurations for CVE-2018-18438

Vendor Product Version Raw CPE
qemu qemu — cpe:2.3:a:qemu:qemu:-:*:*:*:*:*:*:*
redhat enterprise_linux 6.0 cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat openstack 8 cpe:2.3:a:redhat:openstack:8:*:*:*:*:*:*:*
redhat openstack 9 cpe:2.3:a:redhat:openstack:9:*:*:*:*:*:*:*
redhat openstack 10 cpe:2.3:a:redhat:openstack:10:*:*:*:*:*:*:*
redhat openstack 12 cpe:2.3:a:redhat:openstack:12:*:*:*:*:*:*:*
redhat openstack 13 cpe:2.3:a:redhat:openstack:13:*:*:*:*:*:*:*

References for CVE-2018-18438

URL Tags
http://www.openwall.com/lists/oss-security/2018/10/17/3 Mailing List Third Party Advisory
http://www.securityfocus.com/bid/105953 Third Party Advisory VDB Entry
https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg02396.html Mailing List Patch Third Party Advisory
https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg02402.html Mailing List Patch Third Party Advisory
cvelogic Threat Intelligence