CVE-2025-68291 — mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().

Affected: Linux, Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP, Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

In the Linux kernel, the following vulnerability has been resolved:

mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().

syzbot reported divide-by-zero in __tcp_select_window() by MPTCP socket. [0]

We had a similar issue for the bare TCP and fixed in commit 499350a5a6e7 ("tcp: initialize rcv_mss to TCP_MIN_MSS instead of 0").

Let's apply the same fix to mptcp_do_fastclose().

[0]: Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 6068 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336 Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00 00 00 e8 c0 49 01 f8 44 89 e0 99 <f7> 7c 24 1c 41 29 d4 48 bb 00 00 00 00 00 fc ff df e9 80 00 00 00 RSP: 0018:ffffc90003017640 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88807b469e40 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003017730 R08: ffff888033268143 R09: 1ffff1100664d028 R10: dffffc0000000000 R11: ffffed100664d029 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 000055557faa0500(0000) GS:ffff888126135000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f64a1912ff8 CR3: 0000000072122000 CR4: 00000000003526f0 Call Trace: <TASK> tcp_…

USN-8179-1 — linux, linux-aws, linux-aws-6.8, linux-gcp, linux-gke, linux-gkeop, linux-ibm, linux-lowlatency, linux-lowlatency-hwe-6…

Affected: Ubuntu:22.04:LTS: linux-aws-6.8, Ubuntu:22.04:LTS: linux-lowlatency-hwe-6.8, Ubuntu:24.04:LTS: linux, Ubuntu:24.04:LTS: linux-aws, Ubuntu:24.04:LTS: linux-gcp, Ubuntu:24.04:LTS: linux-gke, Ubuntu:24.04:LTS: linux-gkeop, Ubuntu:24.04:LTS: linux-ibm, Ubuntu:24.04:LTS: linux-lowlatency

Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo Rizzo discovered that some AMD Zen processors did not properly verify the signature of CPU microcode. This flaw is known as EntrySign. A privileged attacker could possibly use this issue to cause load malicious CPU microcode causing loss of integrity and confidentiality. (CVE-2024-36347)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - MIPS architecture; - PowerPC architecture; - x86 architecture; - Block layer subsystem; - Cryptographic API; - ACPI drivers; - Network block device driver; - Bluetooth drivers; - Character device driver; - TPM device driver; - Clock framework and drivers; - Data acquisition framework and drivers; - Hardware crypto device drivers; - GPU drivers; - Hardware monitoring drivers; - InfiniBand drivers; - Input Device core drivers; - IOMMU subsystem; - IRQ chip drivers; - Macintosh device drivers; - Multiple devices driver; - Media drivers; - Network drivers; - Mellanox network drivers; - STMicroelectronics network drivers; - Ethernet team driver; - MediaTek network drivers; - NVME drivers; - PA-RISC drivers; - Chrome hardware platform drivers; - x86 platform drivers; - Voltage and Current Regulator drivers; - SCSI subsystem; - SPI subsystem; - Media Oriented Systems Transport…

Most recent entries from all

CVE-2025-68291 — mptcp: Initialise rcv_mss before calling tcp_send_active_reset() in mptcp_do_fastclose().

USN-8179-1 — linux, linux-aws, linux-aws-6.8, linux-gcp, linux-gke, linux-gkeop, linux-ibm, linux-lowlatency, linux-lowlatency-hwe-6…