CVE-2026-71973 (GCVE-0-2026-71973)

Vulnerability from cvelistv5 – Published: 2026-09-29 21:29 – Updated: 2026-09-29 21:29
VLAI
Title
U-Boot before 2026.10-rc4 Integer Overflow in SquashFS Directory Table Allocation
Summary
U-Boot before 2026.10-rc4 contains an integer overflow vulnerability in sqfs_read_directory_table() function when allocating the directory table buffer. Attackers can supply a crafted SquashFS image with an attacker-controlled superblock metablks_count value that causes heap buffer under-allocation and out-of-bounds writes, corrupting heap memory and crashing the bootloader.
Severity
5.2 (Medium)
CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
5.2 (Medium)
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
References
Impacted products
Vendor Product Version CPE status
u-boot u-boot Affected: 0 , < 2026.10-rc4 (custom)
    cpe:2.3:a:denx:u-boot:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-28 00:00
Credits
Shahriyar Jalayeri (ByteRay Ltd.) Mehrun P. Hunter (ByteRay Ltd.)
Show details on NVD website
To clipboard 

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}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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