U-Boot up to 2026.10-rc4 NFS Client net/nfs-common.c nfs_readlink_reply buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.20-

Summaryinfo

A vulnerability categorized as critical has been discovered in U-Boot. This affects the function nfs_readlink_reply of the file net/nfs-common.c of the component NFS Client. The manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2026-74221. The attack may be launched remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in U-Boot. Affected is the function nfs_readlink_reply of the file net/nfs-common.c of the component NFS Client. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-74221 since 08/14/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

Upgrading to version 2026.10-rc5 eliminates this vulnerability. Applying the patch 1c0aff3a5fbfeee7a8948f624e0b8554e6e0d8fd is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.2
CNA Vector (VulnCheck): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: U-Boot 2026.10-rc5
Patch: 1c0aff3a5fbfeee7a8948f624e0b8554e6e0d8fd

Timelineinfo

08/14/2026 CVE reserved
09/29/2026 +46 days Advisory disclosed
09/29/2026 +0 days VulDB entry created
09/29/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-74221 (🔒)
GCVE (CVE): GCVE-0-2026-74221
GCVE (VulDB): GCVE-100-411804

Entryinfo

Created: 09/29/2026 23:45
Changes: 09/29/2026 23:45 (78)
Complete: 🔍
Cache ID: 216::103

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