CVE-2026-48104
June 5, 2026, 8:17 p.m.
4.2
Medium
Description
7-Zip is a file archiver with a high compression ratio. Versions 9.18 through 26.00 contain an uninitialized heap read in the SquashFS archive handler caused by a sparsely populated index array. In the SquashFS handler, _blockToNode is allocated with capacity for every metadata block but populated only when an inode crosses a block boundary, so a crafted image with few inodes spanning many blocks leaves most slots holding raw heap contents (the underlying allocator does not zero-initialize POD storage). When OpenDir looks up an attacker-influenced blockIndex (derived from the RootInode superblock field), it reads two of these uninitialized slots and passes them as the left/right bounds of a binary search over _nodesPos, which dereferences the midpoint without bounds checking; if the resulting value happens to match the search key, the returned index is used to read a full node struct from _nodes whose fields feed further directory parsing, forming a chained OOB read primitive that is heap-layout-dependent and not reliably triggerable. The SquashFS handler is enabled by default in stock 7z.dll and the issue triggers during Open() with no interaction beyond opening the file; impact is denial of service from wild-pointer dereference and potential heap information disclosure, with no write primitive. Version 26.01 fixes the issue.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| 7-zip |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
CWE-125
Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| a | 7-zip | 7-zip | 9.18-26.00 | / | / | / | / | / | / | / |
| a | 7-zip | 7-zip | 26.01 | / | / | / | / | / | / | / |
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: NETWORK
- Attack Complexity: HIGH
- Privileges Required: NONE
- Scope: UNCHANGED
- Confidentiality Impact: LOW
- Integrity Impact: NONE
- Availability Impact: LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L
Timeline
Published: June 5, 2026, 5:16 p.m.
Last Modified: June 5, 2026, 8:17 p.m.
Last Modified: June 5, 2026, 8:17 p.m.
Status : Undergoing Analysis
CVE has been recently published to the CVE List and has been received by the NVD.
More infoSource
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.