bpf: Reject negative offsets for ALU ops (Linux Linux)

CVE-2025-40169
HIGH 7.8

At a glance

Source
NVD
EPSS
EPSS 0.15 % · percentile 4 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Deferred

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Reject negative offsets for ALU ops When verifying BPF programs, the check_alu_op() function validates instructions with ALU operations. The 'offset' field in these instructions is a signed 16-bit integer. The existing check 'insn->off > 1' was intended to ensure the offset is either 0, or 1 for BPF_MOD/BPF_DIV. However, because 'insn->off' is signed, this check incorrectly accepts all negative values (e.g., -1). This commit tightens the validation by changing the condition to '(insn->off != 0 && insn->off != 1)'. This ensures that any value other than the explicitly permitted 0 and 1 is rejected, hardening the verifier against malformed BPF programs.

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Linux · Linuxaffected ec0e2da95f72d4a46050a4d994e4fe471474fd80 < 3bce44b344040e5eef3d64d38b157c15304c0aab ; affected ec0e2da95f72d4a46050a4d994e4fe471474fd80 < 5017c302ca4b2a45149ad64e058fa2d5623c068f ; affected ec0e2da95f72d4a46050a4d994e4fe471474fd80 < 21167bf70dbe400563e189ac632258d35eda38b5 ; affected ec0e2da95f72d4a46050a4d994e4fe471474fd80 < 55c0ced59fe17dee34e9dfd5f7be63cbab207758
Linux · Linuxaffected 6.6 ; unaffected 0 < 6.6 ; unaffected 6.6.112 ≤ 6.6.* ; unaffected 6.12.53 ≤ 6.12.* ; unaffected 6.17.3 ≤ 6.17.* ; unaffected 6.18 ≤ *

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD