CVE-2026-43383
net/tcp-md5: Fix MAC comparison to be constant-time
CRITICAL 9.4
At a glance
- Source
- NVD
- EPSS
- EPSS 0.54 % · percentile 45 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: net/tcp-md5: Fix MAC comparison to be constant-time To prevent timing attacks, MACs need to be compared in constant time. Use the appropriate helper function for this.
Weaknesses (CWE)
- CWE-208 — Observable Timing Discrepancy
References
- https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc
- https://git.kernel.org/stable/c/ff44ec94d4fc8348600a69de0a8fa1102c23bce8
- https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd
- https://git.kernel.org/stable/c/5d305a95130a8d08b9545e47f1e18d29d59866cb
- https://git.kernel.org/stable/c/02669e2a4d207068edce7e8b5fafd85822018ce6
- https://git.kernel.org/stable/c/ae3831b44f477de048287493e184fc3ff913b624
- https://git.kernel.org/stable/c/b502e97e29d791ff7a8051f29a414535739be218
- https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | CRITICAL 9.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H | Linux |
| CVSS 3.1 | CRITICAL 9.4 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-28689
- GCVE · GCVE-0-2026-43383
CERT-FR advisories
- CERTFR-2026-AVI-1029 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1027 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0956 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0954 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0927 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0926 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0898 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0861 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0831 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0696 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 2.6.20 < 5.10.253cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.11 < 6.1.167cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.130cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.78cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.19cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 6.19.9cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc < 821c8751fdeecdeecabeb11704dd33439c9e4bbc ; affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc < ff44ec94d4fc8348600a69de0a8fa1102c23bce8 ; affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc < 345a9530756528d7ca407663d659c3c40e75c3dd ; affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc < 5d305a95130a8d08b9545e47f1e18d29d59866cb ; affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc < 02669e2a4d207068edce7e8b5fafd85822018ce6 ; affected cfb6eeb4c860592edd123fdea908d23c6ad1c7dc < ae3831b44f477de048287493e184fc3ff913b624 |
| Linux · Linux | affected 2.6.20 ; unaffected 0 < 2.6.20 ; unaffected 5.10.253 ≤ 5.10.* ; unaffected 5.15.210 ≤ 5.15.* ; unaffected 6.1.167 ≤ 6.1.* ; unaffected 6.6.130 ≤ 6.6.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |