Is CVE-2026-71973 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-71973 being exploited in the wild.

How severe is CVE-2026-71973?

Medium severity, with a CVSS score of 5.2, published 29 September 2026.

Which products and versions are affected?

Das U-Boot U-Boot before 2026.10-rc4.

Is there a fix for CVE-2026-71973?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-71973 attacked?

It is attacked over the network or with local access, in device firmware.

Am I affected by CVE-2026-71973?

Check whether you run Das U-Boot U-Boot at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-71973: U-Boot integer overflow in SquashFS directory table parsing

CVE-2026-71973 · Severity: medium · CVSS 5.2 · Published 2026-09-29

U-Boot is the open-source bootloader used to initialize embedded systems and IoT devices. A flaw in how it processes SquashFS disk images allows attackers to craft a malicious image that triggers a heap memory corruption, crashing the device during boot. This could be exploited by anyone with access to the boot media or through remote boot services to deny service to affected equipment.

Technologies: Das U-Boot U-Boot. Vendors: Das U-Boot.

Quick answers

Is CVE-2026-71973 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-71973 being exploited in the wild.
How severe is CVE-2026-71973?: Medium severity, with a CVSS score of 5.2, published 29 September 2026.
Which products and versions are affected?: Das U-Boot U-Boot before 2026.10-rc4.
Is there a fix for CVE-2026-71973?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-71973 attacked?: It is attacked over the network or with local access, in device firmware.
Am I affected by CVE-2026-71973?: Check whether you run Das U-Boot U-Boot at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An integer overflow in the sqfs_read_directory_table() function allocates insufficient heap buffer when processing a crafted SquashFS superblock with attacker-controlled metablks_count value, leading to out-of-bounds writes and heap corruption. The vulnerability requires supplying a malicious SquashFS image as boot media or via network boot protocols; no authentication or user interaction is required beyond boot initialization. Exploitation results in bootloader crash and denial of service.

Affected products

Das U-Boot U-Boot before 2026.10-rc4

Timeline

2026-09-29: disclosed

References

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