CVE-2026-71973

MEDIUM 5.2

U-Boot before 2026.10-rc4 Integer Overflow in SquashFS Directory Table Allocation

CVSS Score

5.2

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-190
Vendor	u-boot
Product	u-boot
Published	Sep 29, 2026

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CVSS v3 Breakdown

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

Attack Vector

Physical

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

High

Affected Versions

u-boot / u-boot

0 < 2026.10-rc4

References

NVD ↗ CVE.org ↗ EPSS Data ↗

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

Credits

Shahriyar Jalayeri (ByteRay Ltd.) Mehrun P. Hunter (ByteRay Ltd.)