CVE-2026-43070

In the Linux kernel, the following vulnerability has been resolved: bpf: Reset register ID for BPF_END value tracking When a register undergoes a BPF_END (byte swap) operation, its scalar value is mutated in-place. If this register previously shared a scalar ID with another register (e.g., after an `r1 = r0` assignment), this tie must be broken. Currently, the verifier misses resetting `dst_reg->id` to 0 for BPF_END. Consequently, if a conditional jump checks the swapped register, the verifier incorrectly propagates the learned bounds to the linked register, leading to false confidence in the linked register's value and potentially allowing out-of-bounds memory accesses. Fix this by explicitly resetting `dst_reg->id` to 0 in the BPF_END case to break the scalar tie, similar to how BPF_NEG handles it via `__mark_reg_known`.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0d15c3611a2cc5d08993545d4032055ae10ae2c1	Patch
https://git.kernel.org/stable/c/a17443af874229408ce6b78e2c8a2b5adeb4b7d8	Patch
https://git.kernel.org/stable/c/a3125bc01884431d30d731461634c8295b6f0529	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc4::::::

History

No history.

Information

Published : 2026-05-05 16:16

Updated : 2026-06-17 10:48

NVD link : CVE-2026-43070

Mitre link : CVE-2026-43070

CVE.ORG link : CVE-2026-43070

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-125

Out-of-bounds Read

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