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CVE-2026-48101 (GCVE-0-2026-48101)

Vulnerability from cvelistv5 – Published: 2026-06-05 15:17 – Updated: 2026-06-05 19:38
VLAI
Title
GHSL-2026-117: 7-Zip UEFI Capsule uninitialized heap memory disclosure
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-05 19:38 UTC
CWE
  • CWE-908 - Use of Uninitialized Resource
Assigner
References
Impacted products
Vendor Product Version CPE status
mcmilk 7-Zip Affected: >= 9.21, < 26.01
guessed Create a notification for this product.
Show details on NVD website
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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
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