CVE-2026-53183
mptcp: allow subflow rcv wnd to shrink
HIGH 7.5
At a glance
- Source
- NVD
- EPSS
- EPSS 0.49 % · percentile 42 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: mptcp: allow subflow rcv wnd to shrink In MPTCP connection, the `window` field in the TCP header refers to the MPTCP-level rcv_nxt and it's right edge should not move backward. Such constraint is enforced at DSS option generation time. At the same time, the TCP stack ensures independently that the TCP-level rcv wnd right's edge does not move backward. That in turn causes artificial inflating of the MPTCP rcv window when the incoming data is acked at the TCP level and is OoO in the MPTCP sequence space (or lands in the backlog). As a consequence, the incoming traffic can exceed the receiver rcvbuf size even when the sender is not misbehaving. Prevent such scenario forcibly allowing the TCP subflow to shrink the TCP-level rcv wnd regardless of the current netns setting.
Weaknesses (CWE)
- CWE-400 — Uncontrolled Resource Consumption
References
- https://git.kernel.org/stable/c/bf364b0f10b27679140699821f88af7f01e2a6e3
- https://git.kernel.org/stable/c/b1fd13074f22105deec45aa02283e322733e0c2d
- https://git.kernel.org/stable/c/aa3861f40ac32706d9e97bfac76984613e278788
- https://git.kernel.org/stable/c/653245266913f03fcf21cbca68eed5c197a33e52
- https://git.kernel.org/stable/c/c297a4e65c50a2b807d9309b22615080faffa8f3
- https://git.kernel.org/stable/c/da23be77e1292cd611e736c3aa17da633d7ddce7
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | Linux |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-39274
- GCVE · GCVE-0-2026-53183
CERT-FR advisories
- CERTFR-2026-AVI-1333 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1298 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1286 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1252 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1229 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1203 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1162 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1091 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1064 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0862 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0812 — Multiples vulnérabilités dans Microsoft Azure Linux · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.19 < 6.1.176cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.143cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.94cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.36cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 7.0.13cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected f3589be0c420a3137e5902d15705ced6a36f3f43 < bf364b0f10b27679140699821f88af7f01e2a6e3 ; affected f3589be0c420a3137e5902d15705ced6a36f3f43 < b1fd13074f22105deec45aa02283e322733e0c2d ; affected f3589be0c420a3137e5902d15705ced6a36f3f43 < aa3861f40ac32706d9e97bfac76984613e278788 ; affected f3589be0c420a3137e5902d15705ced6a36f3f43 < 653245266913f03fcf21cbca68eed5c197a33e52 ; affected f3589be0c420a3137e5902d15705ced6a36f3f43 < c297a4e65c50a2b807d9309b22615080faffa8f3 ; affected f3589be0c420a3137e5902d15705ced6a36f3f43 < da23be77e1292cd611e736c3aa17da633d7ddce7 |
| Linux · Linux | affected 5.19 ; unaffected 0 < 5.19 ; unaffected 6.1.176 ≤ 6.1.* ; unaffected 6.6.143 ≤ 6.6.* ; unaffected 6.12.94 ≤ 6.12.* ; unaffected 6.18.36 ≤ 6.18.* |
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 |