Wireshark up to 4.4.14/4.6.4 zlib 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. It has been declared as problematic. Affected is an unknown function of the component zlib Decompression Handler. The manipulation results in improperly controlled sequential memory allocation. This vulnerability is reported as CVE-2026-6535. The attack can be launched remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Wireshark up to 4.4.14/4.6.4. Affected is some unknown processing of the component zlib Decompression Handler. The manipulation with an unknown input leads to a improperly controlled sequential memory allocation vulnerability. CWE is classifying the issue as 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. This is going to have an impact on availability. CVE summarizes:

Dissection engine zlib 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 disclosed by Brendan Coles as 21097. The advisory is available at wireshark.org. This vulnerability is traded as CVE-2026-6535 since 04/17/2026. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not 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). If you want to get best quality of vulnerability data, you may have to visit VulDB.

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

AVACAuCIA
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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: 21097
Researcher: Brendan Coles
Status: Confirmed

CVE: CVE-2026-6535 (🔒)
GCVE (CVE): GCVE-0-2026-6535
GCVE (VulDB): GCVE-100-360282
CERT Bund: WID-SEC-2026-1311 - Wireshark: Mehrere Schwachstellen

Entryinfo

Created: 04/30/2026 12:27
Updated: 07/18/2026 10:20
Changes: 04/30/2026 12:27 (65), 05/01/2026 03:35 (7), 07/18/2026 10:20 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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