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 i
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.
왜 이 VPI인가 (설명가능 · 실험적)
VPI 산정 기준
| 영향도 | 75.00 |
| 악용 신호(추가 악용신호 없음) | ×1.00 |
| VPI | 75.00 |
VPI 공식 vpi-v1 기준