Wireshark up to 4.4.14/4.6.4 LZ77 Decompression improperly controlled sequential memory allocation

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability was found in Wireshark up to 4.4.14/4.6.4 and classified as problematic. This affects an unknown function of the component LZ77 Decompression Handler. Executing a manipulation can lead to improperly controlled sequential memory allocation. This vulnerability is registered as CVE-2026-6533. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Wireshark up to 4.4.14/4.6.4. This vulnerability affects an unknown code of the component LZ77 Decompression Handler. The manipulation with an unknown input leads to a improperly controlled sequential memory allocation vulnerability. The CWE definition for the vulnerability is CWE-1325. The product manages a group of objects or resources and performs a separate memory allocation for each object, but it does not properly limit the total amount of memory that is consumed by all of the combined objects. As an impact it is known to affect availability. CVE summarizes:

Dissection engine LZ77 decompression crash in Wireshark 4.6.0 to 4.6.4 and 4.4.0 to 4.4.14 allows denial of service

The weakness was published by Sharon Brizinov as 21127. The advisory is shared for download at wireshark.org. This vulnerability was named CVE-2026-6533 since 04/17/2026. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 327387 (Amazon Linux 2023 : wireshark-cli, wireshark-devel (ALAS2023-2026-1904)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.4.15 or 4.6.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (327387) and CERT Bund (WID-SEC-2026-1311). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Open Source Wireshark

Productinfo

Type

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (GitLab): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improperly controlled sequential memory allocation
CWE: CWE-1325
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 327387
Nessus Name: Amazon Linux 2023 : wireshark-cli, wireshark-devel (ALAS2023-2026-1904)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Wireshark 4.4.15/4.6.5

Timelineinfo

04/17/2026 CVE reserved
04/30/2026 +13 days Advisory disclosed
04/30/2026 +0 days VulDB entry created
07/18/2026 +79 days VulDB entry last update

Sourcesinfo

Product: wireshark.org

Advisory: 21127
Researcher: Sharon Brizinov
Status: Confirmed

CVE: CVE-2026-6533 (🔒)
GCVE (CVE): GCVE-0-2026-6533
GCVE (VulDB): GCVE-100-360280
CERT Bund: WID-SEC-2026-1311 - Wireshark: Mehrere Schwachstellen

Entryinfo

Created: 04/30/2026 12:27
Updated: 07/18/2026 10:13
Changes: 04/30/2026 12:27 (65), 05/01/2026 00:38 (7), 07/18/2026 10:13 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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