mcmilk 7-Zip up to 26.00 OpenCapsule uninitialized resource

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k2.49

Summaryinfo

A vulnerability labeled as problematic has been found in mcmilk 7-Zip up to 26.00. This impacts the function OpenCapsule. Executing a manipulation can lead to uninitialized resource. This vulnerability appears as CVE-2026-48101. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in mcmilk 7-Zip up to 26.00. This vulnerability affects the function OpenCapsule. The manipulation with an unknown input leads to a uninitialized resource vulnerability. The CWE definition for the vulnerability is CWE-908. The product uses or accesses a resource that has not been initialized. As an impact it is known to affect confidentiality. CVE summarizes:

7-Zip is a file archiver with a high compression ratio. Versions 9.21 through 26.00 contain an An uninitialized memory disclosure vulnerability in the UEFI capsule (.scap) parser in 7-Zip. The OpenCapsule function allocates a heap buffer of attacker-declared CapsuleImageSize (up to 1 GiB) without zero-initialization, then reads the file contents into it with ReadStream_FALSE whose return value is silently discarded. If the file is truncated, the unread tail of the buffer retains uninitialized heap memory, which is then exposed as extracted file content via GetStream. Version 26.0.1 fixes the issue.

The advisory is available at securitylab.github.com. This vulnerability was named CVE-2026-48101 since 05/20/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

Upgrading to version 26.01 eliminates this vulnerability.

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

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Uninitialized resource
CWE: CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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 26.01

Timelineinfo

05/20/2026 CVE reserved
06/05/2026 +16 days Advisory disclosed
06/05/2026 +0 days VulDB entry created
06/05/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: GHSL-2026-115
Status: Confirmed

CVE: CVE-2026-48101 (🔒)
GCVE (CVE): GCVE-0-2026-48101
GCVE (VulDB): GCVE-100-368938

Entryinfo

Created: 06/05/2026 18:50
Changes: 06/05/2026 18:50 (65)
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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