Vulnerability · Published Sep 29, 2026 · Assigned by VulnCheck

CVE-2026-74220U-Boot before 2026.10-rc5 Buffer Overflow via NFS READ Reply

High 8.2

In plain English

A high-severity security flaw in u-boot from u-boot. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.2High
Exploit odds (30 days)0.3%top 73.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

U-Boot before 2026.10-rc5 contains a buffer overflow in nfs_read_reply() function in net/nfs-common.c that allows attackers to corrupt memory by supplying crafted NFS READ reply lengths. A malicious NFS server can exploit signed integer handling to bypass length validation and write far past the destination buffer, crashing the bootloader or corrupting memory.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12u-bootno fix listedDEBIAN-CVE-2026-74220
Debian:13u-bootno fix listedDEBIAN-CVE-2026-74220
Debian:14u-bootno fix listedDEBIAN-CVE-2026-74220
Ubuntu:22.04:LTSu-boot2022.01+dfsg-2ubuntu2.9USN-8930-1
Ubuntu:22.04:LTSu-boot2022.01+dfsg-2ubuntu2.9UBUNTU-CVE-2026-74220
Ubuntu:24.04:LTSu-boot2025.10-0ubuntu0.24.04.4UBUNTU-CVE-2026-74220
Ubuntu:24.04:LTSu-boot2025.10-0ubuntu0.24.04.4USN-8930-1
Ubuntu:26.04:LTSu-boot2025.10-0ubuntu2.2UBUNTU-CVE-2026-74220
Ubuntu:26.04:LTSu-boot2025.10-0ubuntu2.2USN-8930-1
Ubuntu:26.10u-boot2025.10-0ubuntu6UBUNTU-CVE-2026-74220
Ubuntu:26.10u-boot2025.10-0ubuntu6USN-8930-2
Ubuntu:22.04:LTSu-boot-nezhano fix listedUBUNTU-CVE-2026-74220
Ubuntu:24.04:LTSu-boot-nezhano fix listedUBUNTU-CVE-2026-74220

Affected products (as reported)

VendorProductVersions
u-boot u-boot 0 – before 2026.10-rc5

Weakness: CWE-195 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H

References