cbcvebase.
CVE-2021-47593
published 2024-06-19

CVE-2021-47593: In the Linux kernel, the following vulnerability has been resolved: mptcp: clear 'kern' flag from fallback sockets The mptcp ULP extension relies on…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.25%
15.9th percentile
In the Linux kernel, the following vulnerability has been resolved: mptcp: clear 'kern' flag from fallback sockets The mptcp ULP extension relies on sk->sk_sock_kern being set correctly: It prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); from working for plain tcp sockets (any userspace-exposed socket). But in case of fallback, accept() can return a plain tcp sk. In such case, sk is still tagged as 'kernel' and setsockopt will work. This will crash the kernel, The subflow extension has a NULL ctx->conn mptcp socket: BUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0 Call Trace: tcp_data_ready+0xf8/0x370 [..]

Affected

12 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.15-1 (bookworm)linux 5.15.15-1 (bookworm)
linuxlinux——
linuxlinux>= cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be < 451f1eded7f56e93aaf52eb547ba97742d9c0e97451f1eded7f56e93aaf52eb547ba97742d9c0e97
linuxlinux>= cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be < c26ac0ea3a91c210cf90452e625dc441adf3e549c26ac0ea3a91c210cf90452e625dc441adf3e549
linuxlinux>= cf7da0d66cc1a2a19fc5930bb746ffbb2d4cd1be < d6692b3b97bdc165d150f4c1505751a323a80717d6692b3b97bdc165d150f4c1505751a323a80717
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.92-15.10.92-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 0 < 5.15.15-15.15.15-1
linuxlinux_kernel>= 5.11 < 5.15.115.15.11
linuxlinux_kernel>= 5.6 < 5.10.885.10.88

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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