// For flags

CVE-2023-3354

Improper i/o watch removal in tls handshake can lead to remote unauthenticated denial of service

Severity Score

7.5
*CVSS v3.1

Exploit Likelihood

< 1%
*EPSS

Affected Versions

9
*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

A flaw was found in the QEMU built-in VNC server. When a client connects to the VNC server, QEMU checks whether the current number of connections crosses a certain threshold and if so, cleans up the previous connection. If the previous connection happens to be in the handshake phase and fails, QEMU cleans up the connection again, resulting in a NULL pointer dereference issue. This could allow a remote unauthenticated client to cause a denial of service.

Gaoning Pan and Xingwei Li discovered that QEMU incorrectly handled the USB xHCI controller device. A privileged guest attacker could possibly use this issue to cause QEMU to crash, leading to a denial of service. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. It was discovered that QEMU incorrectly handled the TCG Accelerator. A local attacker could use this issue to cause QEMU to crash, leading to a denial of service, or possibly execute arbitrary code and escalate privileges. This issue only affected Ubuntu 20.04 LTS.

*Credits: Red Hat would like to thank jiangyegen (Huawei Vulnerability Management Center) and yexiao7 (Huawei Vulnerability Management Center) for reporting this issue.
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2023-06-21 CVE Reserved
  • 2023-07-11 CVE Published
  • 2025-02-13 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-476: NULL Pointer Dereference
CAPEC
Affected Vendors, Products, and Versions (9)