CVE-2026-71973

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.

CVSS v3 5.2 MEDIUM

5.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.9 / Impact : 4.2

Attack Vector PHYSICAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/u-boot/u-boot
https://github.com/u-boot/u-boot/blob/v2026.07/fs/squashfs/sqfs.c#L814
https://github.com/u-boot/u-boot/commit/561ae28cb56a082cfa90c1c421c4955bc215470b
https://www.vulncheck.com/advisories/u-boot-before-2026.10-rc4-integer-overflow-in-squashfs-directory-table-allocation

Configurations

No configuration.

History

29 Sep 2026, 22:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-29 22:18

Updated : 2026-10-02 13:17

NVD link : CVE-2026-71973

Mitre link : CVE-2026-71973

CVE.ORG link : CVE-2026-71973

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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