CVE-2026-96423Public exploitHinoki check available

Application crash via stale X11 keysym width

Published Sep 29, 2026 · Updated Sep 29, 2026

Out-of-bounds read in Wireshark 4.4.0 through 4.4.18 and 4.6.0 through 4.6.8 allows attackers to crash analysis of crafted X11 traffic. In the X11 dissector, keycode2keysymString() indexes a cached keysym array using a stale global width rather than that array's allocated length. The dissector is enabled by default; the trigger requires analysis of injected traffic or a crafted capture file, and the upstream report also demonstrates disclosure of an adjacent heap word in decoded output.

CVSS severityUnavailable
Unscored
EPSS probability0.13%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Out-of-bounds read in Wireshark 4.4.0 through 4.4.18 and 4.6.0 through 4.6.8 allows attackers to crash analysis of crafted X11 traffic. In the X11 dissector, keycode2keysymString() indexes a cached keysym array using a stale global width rather than that array's allocated length. The dissector is enabled by default; the trigger requires analysis of injected traffic or a crafted capture file, and the upstream report also demonstrates disclosure of an adjacent heap word in decoded output.

The record

CVE
CVE-2026-96423
Published
Sep 29, 2026
Updated
Sep 29, 2026
Vendor
Wireshark Foundation
Product
Wireshark
Classifications
CWE-122, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 29, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 29, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.4.0 <4.4.19
  2. Affected versionversion=4.6.0 <4.6.9

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Wireshark Foundation · Wiresharkversion=4.4.0 <4.4.19; version=4.6.0 <4.6.9

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

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

Technologies

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