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.

7zip-26.02-2.1 on GA media

Security update for 7zip

Affected: Ubuntu:14.04:LTS: p7zip, Ubuntu:16.04:LTS: p7zip, Ubuntu:18.04:LTS: p7zip, Ubuntu:20.04:LTS: p7zip, Ubuntu:22.04:LTS: p7zip, Ubuntu:Pro:22.04:LTS: 7zip, Ubuntu:Pro:24.04:LTS: 7zip, Ubuntu:25.10: 7zip, Ubuntu:26.04:LTS: 7zip

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.

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in 7-Zip ausnutzen, um Speicherinhalte offenzulegen, einen Denial-of-Service auszulösen oder beliebigen Code auszuführen.