CVE-2026-43070

7.8 HIGH
Published: May 05, 2026 Modified: May 29, 2026
View on NVD

Description

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`.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/0d15c3611a2cc5d08993545d4032055ae10ae2c1
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/a17443af874229408ce6b78e2c8a2b5adeb4b7d8
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/a3125bc01884431d30d731461634c8295b6f0529
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.8 / 10.0
EPSS (Exploit Probability)
0.1%
2th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

linux