mcmilk 7-Zip up to 26.00 SquashFS Fragment out-of-bounds

Summaryinfo

A vulnerability identified as problematic has been detected in mcmilk 7-Zip up to 26.00. Impacted is an unknown function of the component SquashFS Fragment Handler. This manipulation causes out-of-bounds. This vulnerability appears as CVE-2026-48092. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in mcmilk 7-Zip up to 26.00 and classified as problematic. Affected by this vulnerability is some unknown functionality of the component SquashFS Fragment Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect availability. The summary by CVE is:

7-Zip is a file archiver with a high compression ratio. Versions 9.34 through 26.00 contain a heap memory disclosure via SquashFS fragment offset integer overflow on 32-bit builds. 32-bit integer overflow in the SquashFS ReadBlock function allows an attacker-controlled node.Offset value to bypass the fragment bounds check, causing memcpy to read heap memory preceding the cache buffer into the extracted file. The vulnerability is exploitable only on 32-bit builds of 7-Zip where size_t is 32 bits, allowing the addition offsetInBlock + blockSize to wrap modulo 2³². On 64-bit builds the addition is promoted to 64 bits and the check correctly rejects the input. Version 26.01 patches the issue.

It is possible to read the advisory at securitylab.github.com. This vulnerability is known as CVE-2026-48092 since 05/20/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 26.01 eliminates this vulnerability.

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Productinfo

Type

• File Compression Software

Vendor

• mcmilk

Name

• 7-Zip

Version

• 26

CPE 2.3info

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CPE 2.2info

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