CVE-2025-11234Public exploitNetwork attack vector

Pre-auth crash via leaked handshake callback

Published Oct 3, 2025 · Updated Oct 3, 2025

Use-after-free in QEMU 2.6.0 through 10.1.1 allows remote attackers to crash the VNC server via an incomplete WebSocket handshake. QIOChannelWebsock fails to remove its handshake GSource when the channel is freed, so the pending callback later dereferences the released channel. The VNC WebSocket listener must be enabled and network-reachable, but the callback can be triggered before VNC client authentication.

CVSS severity7.5
High
EPSS probability0.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in QEMU 2.6.0 through 10.1.1 allows remote attackers to crash the VNC server via an incomplete WebSocket handshake. QIOChannelWebsock fails to remove its handshake GSource when the channel is freed, so the pending callback later dereferences the released channel. The VNC WebSocket listener must be enabled and network-reachable, but the callback can be triggered before VNC client authentication.

The record

CVE
CVE-2025-11234
Published
Oct 3, 2025
Updated
Oct 3, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-416, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 3, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5Red Hat, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-416Use After Free
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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