7-Zip up to 26.02 SquashFS v4 archive handler SquashfsHandler.cpp no_ids uninitialized pointer

CVSS Meta Temp Score
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CTI Interest Score
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4.1$0-$5k0.41

Summaryinfo

A vulnerability was found in 7-Zip up to 26.02. It has been classified as problematic. Affected by this issue is some unknown functionality of the file SquashfsHandler.cpp of the component SquashFS v4 archive handler. This manipulation of the argument no_ids causes uninitialized pointer. This vulnerability appears as CVE-2026-104086. The attack requires local access. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in 7-Zip up to 26.02. It has been declared as problematic. Affected by this vulnerability is an unknown code block of the file SquashfsHandler.cpp of the component SquashFS v4 archive handler. The manipulation of the argument no_ids with an unknown input leads to a uninitialized pointer vulnerability. The CWE definition for the vulnerability is CWE-824. The product accesses or uses a pointer that has not been initialized. As an impact it is known to affect confidentiality. The summary by CVE is:

7-Zip before 26.03 contains an uninitialized memory disclosure vulnerability in the SquashFS v4 archive handler (SquashfsHandler.cpp) that allows attackers to leak heap memory by crafting a malicious archive where the superblock’s no_ids field is set so that the final metadata block’s expected size is miscomputed and bypasses the size validation check. By listing or extracting the crafted archive, attackers can cause the application to return uninitialized heap memory as the kpidUserId and kpidGroupId properties, exposing potentially sensitive process memory contents to the user.

The advisory is shared at sourceforge.net. This vulnerability is known as CVE-2026-104086 since 10/01/2026. The exploitation appears to be easy. An attack has to be approached locally. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

Upgrading to version 26.03 eliminates this vulnerability.

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Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.1
VulDB Meta Temp Score: 4.1

VulDB Base Score: 2.8
VulDB Temp Score: 2.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

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

CVSSv2info

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

Exploitinginfo

Class: Uninitialized pointer
CWE: CWE-824 / CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: 7-Zip 26.03

Timelineinfo

10/01/2026 CVE reserved
10/14/2026 +13 days Advisory disclosed
10/14/2026 +0 days VulDB entry created
10/14/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: sourceforge.net
Status: Confirmed

CVE: CVE-2026-104086 (🔒)
GCVE (CVE): GCVE-0-2026-104086
GCVE (VulDB): GCVE-100-419893

Entryinfo

Created: 10/14/2026 16:32
Changes: 10/14/2026 16:32 (77)
Complete: 🔍
Cache ID: 216::103

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