CVE-2023-6693

Publication date 2 January 2024

Last updated 26 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

5.3 · Medium

Score breakdown

Description

A stack based buffer overflow was found in the virtio-net device of QEMU. This issue occurs when flushing TX in the virtio_net_flush_tx function if guest features VIRTIO_NET_F_HASH_REPORT, VIRTIO_F_VERSION_1 and VIRTIO_NET_F_MRG_RXBUF are enabled. This could allow a malicious user to overwrite local variables allocated on the stack. Specifically, the `out_sg` variable could be used to read a part of process memory and send it to the wire, causing an information leak.

Read the notes from the security team

Status

Package Ubuntu Release Status
qemu 24.04 LTS noble
Not affected
23.10 mantic Ignored end of life, was needed
23.04 lunar Ignored end of life, was deferred [2024-01-12]
22.04 LTS jammy
Fixed 1:6.2+dfsg-2ubuntu6.22
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes

mdeslaur

introduced in v5.1.0-rc0

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
qemu

Severity score breakdown

Parameter Value
Base score 5.3 · Medium
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality Low
Integrity impact Low
Availability impact Low
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

References

Related Ubuntu Security Notices (USN)

Other references