CVE-2025-21680

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

pktgen: Avoid out-of-bounds access in get_imix_entries

Passing a sufficient amount of imix entries leads to invalid access to the

pkt_dev->imix_entries array because of the incorrect boundary check.

UBSAN: array-index-out-of-bounds in net/core/pktgen.c:874:24

index 20 is out of range for type 'imix_pkt [20]'

CPU: 2 PID: 1210 Comm: bash Not tainted 6.10.0-rc1 #121

Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)

Call Trace:

<TASK>

dump_stack_lvl lib/dump_stack.c:117

__ubsan_handle_out_of_bounds lib/ubsan.c:429

get_imix_entries net/core/pktgen.c:874

pktgen_if_write net/core/pktgen.c:1063

pde_write fs/proc/inode.c:334

proc_reg_write fs/proc/inode.c:346

vfs_write fs/read_write.c:593

ksys_write fs/read_write.c:644

do_syscall_64 arch/x86/entry/common.c:83

entry_SYSCALL_64_after_hwframe arch/x86/entry/entry_64.S:130

Found by Linux Verification Center (linuxtesting.org) with SVACE.

[ fp: allow to fill the array compl

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References