Bug 2498162 (CVE-2026-29009)

Summary: CVE-2026-29009 u-boot: U-Boot: Memory corruption via NFS readlink buffer overflow
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: urgent Docs Contact:
Priority: urgent    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in U-Boot. A buffer overflow vulnerability exists in the `nfs_readlink_reply()` function when the Network File System (NFS) command is enabled. A malicious or compromised NFS server can exploit this by sending multiple relative symlink targets, exceeding the buffer's capacity. This can lead to memory corruption and potentially allow an attacker to control the NFS client's state machine.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2499671, 2499672    
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Description OSIDB Bzimport 2026-07-08 17:02:53 UTC 
U-Boot through 2026.04-rc3 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the 2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without cumulative length validation. Attackers can send two or more READLINK responses containing relative symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially achieving memory corruption and control over the NFS client state machine.