CVE-2026-95391

Description

A flaw was found in the ZigBee ZCL protocol dissector in Wireshark. This issue occurs when malformed packets are decoded from a pcap file or the network, causing a use-after-free, resulting in a denial of service.

Statement

This issue will cause a crash in Wireshark with no other security impact. Also, this flaw can only be exploited when malformed packets from a pcap file or the network are processed. Due to these reasons, this vulnerability has been rated with a moderate severity.

Mitigation

If the ZigBee ZCL protocol dissector is not being used, it can be disabled via the "Enabled Protocols" dialog box in the Wireshark GUI application. This will also disable the protocol dissector when using "tshark", the command line tool.

See the links below for instructions to disable a protocol in Wireshark, specifically the "Control Protocol Dissection" section and the "disabled_protos" configuration file option.

https://www.wireshark.org/docs/wsug_html_chunked/ChCustProtocolDissectionSection.html
https://www.wireshark.org/docs/wsug_html_chunked/ChAppFilesConfigurationSection.html

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.5N/A5.5
Attack VectorLocalN/ALocal
Attack ComplexityLowN/ALow
Privileges RequiredNoneN/ANone
User InteractionRequiredN/ARequired
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/ANone
Integrity ImpactNoneN/ANone
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

cve.org: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

Integrity

Technical Impact: Modify Memory

The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.

Confidentiality

Technical Impact: Read Memory

Read operations on freed memory can sometimes leak sensitive information instead of causing a crash

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Frequently Asked Questions

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