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 4.0

5.2CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

5.2CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

EPSS

0.2% chance of exploitation in the next 30 days; higher than 8% of CVEs (scores of 2026-10-25)

CWE

CWE-190

Published

2026-09-29

Modified

2026-10-02

Record from

the NVD, synced 2026-10-19

References

• 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

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