Enable TCP-SYN Cookie Protection

TCP-SYN cookie protection mitigates the impact of SYN flood attacks on the system. When an attacker launches a SYN flood attack, the half-open connection queue in the kernel is quickly exhausted to block valid connections. If SYN cookie is enabled, the system can still accept valid connections ev...

CVE-2023-53121 tcp: tcp_make_synack() can be called from process context

In the Linux kernel, the following vulnerability has been resolved: tcp: tcpmakesynack can be called from process context tcprtxsynack now could be called in process context as explained in 0a375c822497 "tcp: tcprtxsynack can be called from process context". tcprtxsynack might call tcpmakesynack,...

UBUNTU-CVE-2025-23145

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix NULL pointer in canacceptnewsubflow When testing valkey benchmark tool with MPTCP, the kernel panics in 'mptcpcanacceptnewsubflow' because subflowreq-msk is NULL. Call trace: mptcpcanacceptnewsubflow...

CVE-2025-23145

Summary (CVE-2025-23145) : Linux kernel MPTCP component fix for a NULL pointer dereference in can_accept_new_subflow when subflow_req->msk is NULL. The issue could occur when a SYN-ACK is received twice in quick succession and the ownership of subflow_req->msk is transferred to the first su...

PT-2025-38559

Name of the Vulnerable Software and Affected Versions Linux kernel affected versions not specified Description A memory leak exists in the TCP-AO failure handling for IPv6 within the Linux kernel. Specifically, when tcp ao copy all matching fails in tcp v6 syn recv sock, the function exits withou...

Anatomy of a SYN-ACK Attack

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PT-2025-18399

Name of the Vulnerable Software and Affected Versions Linux kernel affected versions not specified Description A vulnerability has been resolved in the Linux kernel related to the MPTCP protocol. The issue occurs when the kernel panics in 'mptcp can accept new subflow' due to a NULL pointer...

Linux Distros Unpatched Vulnerability : CVE-2023-52700

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - tipc: fix kernel warning when sending SYN message When sending a SYN message, this kernel stack trace is observed: ... 13.396352 RIP: 0010:copyfromiter+0xb4/0x5...

Linux Distros Unpatched Vulnerability : CVE-2023-1206

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - A hash collision flaw was found in the IPv6 connection lookup table in the Linux kernel's IPv6 functionality when a user makes a new kind of SYN flood attack. A...

Linux Distros Unpatched Vulnerability : CVE-2017-5972

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - The TCP stack in the Linux kernel 3.x does not properly implement a SYN cookie protection mechanism for the case of a fast network connection, which allows remo...

CVE-2022-49372

CVE-2022-49372 affects the Linux kernel where tcp_rtx_synack() can be invoked from process context during a Fast Open TCP backlog/backlog processing sequence when CONFIG_DEBUG_PREEMPT is enabled. The issue arises as a SYN retransmit is processed in process context, cooking a SYN-ACK in that conte...

CVE-2022-49372

In the Linux kernel, the following vulnerability has been resolved: tcp: tcprtxsynack can be called from process context Laurent reported the enclosed report 1 This bug triggers with following coditions: 0 Kernel built with CONFIGDEBUGPREEMPT=y 1 A new passive FastOpen TCP socket is created. This...

Siemens SIMATIC and SCALANCE Devices Uncontrolled Resource Consumption (CVE-2023-1206)

A hash collision flaw was found in the IPv6 connection lookup table in the Linux kernel's IPv6 functionality when a user makes a new kind of SYN flood attack. A user located in the local network or with a high bandwidth connection can increase the CPU usage of the server that accepts IPV6...

kernel: TCP-spoofed ghost ACKs and leak leak initial sequence number

A flaw was found in the Linux kernel. Two TCP spoofing primitives exist where an attacker can brute force the server-chosen send window by acknowledging data that was never sent, called "ghost ACKs." There are side channels that also allow the attacker to leak the otherwise secret server-chosen...

Cisco IP Phone Improper Restriction of Operations within the Bounds of a Memory Buffer (CVE-2006-0179)

The Cisco IP Phone 7940 allows remote attackers to cause a denial of service reboot via a large amount of TCP SYN packets syn flood to arbitrary ports, as demonstrated to port 80. This plugin only works with Tenable.ot. Please visit https://www.tenable.com/products/tenable-ot for more information...

CVE-2024-50154

A use-after-free UAF vulnerability was found and fixed in the Linux kernel's TCP subsystem related to request socket reqsk timers during handshake handling. This issue stems from a race condition caused by relying on timerpending in reqskqueueunlink. This could result in the timer continuing to r...

CVE-2024-50154 tcp/dccp: Don't use timer_pending() in reqsk_queue_unlink().

In the Linux kernel, the following vulnerability has been resolved: tcp/dccp: Don't use timerpending in reqskqueueunlink. Martin KaFai Lau reported use-after-free 0 in reqsktimerhandler. """ We are seeing a use-after-free from a bpf prog attached to tracetcpretransmitsynack. The program passes th...

CVE-2024-50154

The CVE-2024-50154 vulnerability is in the Linux kernel. Root cause: a use-after-free can occur in reqsk_timer_handler() when a race around timer_pending() in reqsk_queue_unlink() allows a timer to fire after the socket is closed. The fix prevents del_timer_sync() from being missed by removing ti...

DEBIAN-CVE-2024-50083

In the Linux kernel, the following vulnerability has been resolved: tcp: fix mptcp DSS corruption due to large pmtu xmit Syzkaller was able to trigger a DSS corruption: TCP: requestsocksubflowv4: Possible SYN flooding on port :::20002. Sending cookies. ------------ cut here ------------ WARNING:...

UBUNTU-CVE-2024-50083

In the Linux kernel, the following vulnerability has been resolved: tcp: fix mptcp DSS corruption due to large pmtu xmit Syzkaller was able to trigger a DSS corruption: TCP: requestsocksubflowv4: Possible SYN flooding on port :::20002. Sending cookies. ------------ cut here ------------ WARNING:...