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.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.3, indicating it can be exploited remotely over the network with relatively low complexity though user interaction is required and does not require pre-existing privileges . The vulnerability impacts and limited availability for affected systems. Impacting 1 product from 7-zip organizations running these solutions should prioritize assessment and patching.
Reported in 2026, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2026-06-05T15:16:53.380
2026-06-17T10:54:50.893
Modified
CVSSv3.1: 4.3 (MEDIUM)
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For 7-zip's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.