CVE-2023-4135: Out-of-bounds read information disclosure vulnerability

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-08-04 · updated 2026-06-17
Weakness: CWE-125

Description

A heap out-of-bounds memory read flaw was found in the virtual nvme device in QEMU. The QEMU process does not validate an offset provided by the guest before computing a host heap pointer, which is used for copying data back to the guest. Arbitrary heap memory relative to an allocated buffer can be disclosed.

Affected products

Fedoraproject Fedora: 38
QEMU: from 8.0.0 before 8.1.0; 8.1.0-rc0, 8.1.0-rc1, 8.1.0-rc2 — fixed in 8.1.0

How to fix

Upgrade to a fixed version: QEMU 8.1.0. Check the vendor advisory for mitigations.

References

https://access.redhat.com/security/cve/CVE-2023-4135
https://bugzilla.redhat.com/show_bug.cgi?id=2229101
https://security.netapp.com/advisory/ntap-20230915-0012/
https://www.zerodayinitiative.com/advisories/ZDI-CAN-21521
https://access.redhat.com/security/cve/CVE-2023-4135
https://bugzilla.redhat.com/show_bug.cgi?id=2229101
https://security.netapp.com/advisory/ntap-20230915-0012/
https://www.zerodayinitiative.com/advisories/ZDI-CAN-21521

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