7-Zip < 26.03 SquashFS Uninitialized Memory Disclosure via UID/GID Table
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.
CVE-2026-104086
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-104086
7-Zip
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "7-Zip",
"product": "7-Zip",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "26.03",
"versionType": "custom"
}
],
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-104086
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #39975 · Revision 1
- Added to Heist Feed
- Publisher date