CVE-2026-74221

U-Boot before 2026.10-rc5 contains a buffer overflow in nfs_readlink_reply() function in net/nfs-common.c when processing NFS server responses. A malicious NFS server can send crafted READLINK replies with negative or oversized symlink length values to corrupt memory and crash the bootloader.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

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/net/nfs-common.c#L643
https://github.com/u-boot/u-boot/commit/1c0aff3a5fbfeee7a8948f624e0b8554e6e0d8fd
https://www.vulncheck.com/advisories/u-boot-before-2026.10-rc5-buffer-overflow-via-nfs-readlink

Configurations

No configuration.

History

29 Sep 2026, 22:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-29 22:18

Updated : 2026-09-30 16:40

NVD link : CVE-2026-74221

Mitre link : CVE-2026-74221

CVE.ORG link : CVE-2026-74221

JSON object : View

Products Affected

No product.

CWE

CWE-195

Signed to Unsigned Conversion Error

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