CVE-2026-53183
published 2026-06-25CVE-2026-53183: 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…
PriorityP341high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.48%
38.7th percentile
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.
Affected
19 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= f3589be0c420a3137e5902d15705ced6a36f3f43 < bf364b0f10b27679140699821f88af7f01e2a6e3 | bf364b0f10b27679140699821f88af7f01e2a6e3 |
| linux | linux | >= f3589be0c420a3137e5902d15705ced6a36f3f43 < b1fd13074f22105deec45aa02283e322733e0c2d | b1fd13074f22105deec45aa02283e322733e0c2d |
| linux | linux | >= f3589be0c420a3137e5902d15705ced6a36f3f43 < aa3861f40ac32706d9e97bfac76984613e278788 | aa3861f40ac32706d9e97bfac76984613e278788 |
| linux | linux | >= f3589be0c420a3137e5902d15705ced6a36f3f43 < 653245266913f03fcf21cbca68eed5c197a33e52 | 653245266913f03fcf21cbca68eed5c197a33e52 |
| linux | linux | >= f3589be0c420a3137e5902d15705ced6a36f3f43 < c297a4e65c50a2b807d9309b22615080faffa8f3 | c297a4e65c50a2b807d9309b22615080faffa8f3 |
| linux | linux | >= f3589be0c420a3137e5902d15705ced6a36f3f43 < da23be77e1292cd611e736c3aa17da633d7ddce7 | da23be77e1292cd611e736c3aa17da633d7ddce7 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 5.19 < 6.1.176 | 6.1.176 |
| linux | linux_kernel | >= 6.13 < 6.18.36 | 6.18.36 |
| linux | linux_kernel | >= 6.19 < 7.0.13 | 7.0.13 |
| linux | linux_kernel | >= 6.2 < 6.6.143 | 6.6.143 |
| linux | linux_kernel | >= 6.7 < 6.12.94 | 6.12.94 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vendor_redhat5.5MEDIUM
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GHSA
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
ghsa_unreviewed·2026-06-25
CVE-2026-53183 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
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-lev
Red Hat
kernel: mptcp: allow subflow rcv wnd to shrink
vendor_redhat·2026-06-25·CVSS 5.5
CVE-2026-53183 [MEDIUM] CWE-131 kernel: mptcp: allow subflow rcv wnd to shrink
kernel: mptcp: allow subflow rcv wnd to shrink
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 all
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/653245266913f03fcf21cbca68eed5c197a33e52https://git.kernel.org/stable/c/aa3861f40ac32706d9e97bfac76984613e278788https://git.kernel.org/stable/c/b1fd13074f22105deec45aa02283e322733e0c2dhttps://git.kernel.org/stable/c/bf364b0f10b27679140699821f88af7f01e2a6e3https://git.kernel.org/stable/c/c297a4e65c50a2b807d9309b22615080faffa8f3https://git.kernel.org/stable/c/da23be77e1292cd611e736c3aa17da633d7ddce7
2026-06-25
Published