GHSL-2026-117: 7-Zip UEFI Capsule uninitialized heap memory disclosure_CVE-2026-48101

6.5 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Description

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.

Basic Information

ID CVE-2026-48101

Source GitHub_M

Published Jun 5, 2026 at 15:17

Affected Product

Vendor mcmilk

Product 7-Zip

Version >= 9.21, < 26.01

Affected Versions mcmilk 7-Zip >= 9.21, < 26.01

CWE Classification

CWE-908

References

securitylab.github.com /advisories/GHSL-2026-115_GHSL-2026-122_7-zip/

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    "published": "2026-06-05T15:17:38.676Z",
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