Cloudanix VulnDB

CVE-2024-56643

Medium · 5.5

CVSS

5.5

EPSS

0.2%

Published

Dec 27, 2024

CISA due date

—

Cloudanix analysis

Schedule a fix SSVC: Track

A bug in how the system handles certain network connection settings could slowly use up memory until services slow down or stop working.

Exploitation
Remote Authenticated
Attacker needs
Low Privilege
Complexity
Moderate
Impact
Denial Of Service
Component
OS kernel
Class
Memory Corruption
Remediation
Patch
Effort
Medium
Patch risk
Low

What it actually does

Memory leak in DCCP feature negotiation: when dccp_feat_push_confirm() fails after accepting a new SP feature value in the 'entry == NULL' branch, memory allocated by dccp_feat_clone_sp_val() is never freed.

Why it matters to the business

Systems relying on DCCP can experience gradual memory exhaustion under sustained network traffic, leading to performance degradation, service instability, or eventual denial of service; high ecosystem prevalence of the Linux kernel increases exposure across servers and embedded devices.

How an attack unfolds

An attacker sends specially crafted DCCP packets that reach dccp_feat_change_recv and trigger the failure path after value acceptance; repeated triggering leaks small allocations, exhausting kernel memory. General Linux kernel exploitation campaigns by espionage and financially motivated actors provide context for similar kernel memory issues.

How to fix it

Update the Linux kernel to commit 623be080ab3c13d71570bd32f7202a8efa8e2252 or later; for affected webkit2gtk packages on Ubuntu 16.04 LTS upgrade to version 2.12.5-0ubuntu0.16.04.1. Reboot after kernel updates and verify DCCP is disabled if unused.

How to confirm the fix worked

Confirm kernel version contains the fix commit; run kmemleak or similar memory debugging tools under DCCP traffic; inspect feat.c for the added cleanup on push_confirm failure.

Typical attack path

  1. Establish DCCP connection to target
  2. Send feature negotiation options that exercise the SP value acceptance branch
  3. Force dccp_feat_push_confirm() to fail
  4. Repeat to accumulate unreferenced allocations
  5. Monitor for memory pressure or system instability

How to detect it

Review kernel logs and kmemleak reports for unreferenced objects allocated in dccp_feat_clone_sp_val; correlate with DCCP traffic in netfilter or socket logs; look for repeated calls through dccp_feat_parse_options in process traces.

What your security team should do

  • Prioritize kernel upgrade on all systems exposing DCCP or reachable via untrusted networks
  • Disable DCCP protocol support via kernel config or sysctl where not required
  • Monitor EPSS and KEV status for changes indicating increased exploitability
  • Include the fixed commit in patch management and automated deployment pipelines

The record

In the Linux kernel, the following vulnerability has been resolved: dccp: Fix memory leak in dccp_feat_change_recv If dccp_feat_push_confirm() fails after new value for SP feature was accepted without reconciliation ('entry == NULL' branch), memory allocated for that value with dccp_feat_clone_sp_val() is never freed. Here is the kmemleak stack for this: unreferenced object 0xffff88801d4ab488 (size 8): comm "syz-executor310", pid 1127, jiffies 4295085598 (age 41.666s) hex dump (first 8 bytes): 01 b4 4a 1d 80 88 ff ff ..J..... backtrace: [<00000000db7cabfe>] kmemdup+0x23/0x50 mm/util.c:128 [<0000000019b38405>] kmemdup include/linux/string.h:465 [inline] [<0000000019b38405>] dccp_feat_clone_sp_val net/dccp/feat.c:371 [inline] [<0000000019b38405>] dccp_feat_clone_sp_val net/dccp/feat.c:367 [inline] [<0000000019b38405>] dccp_feat_change_recv net/dccp/feat.c:1145 [inline] [<0000000019b38405>] dccp_feat_parse_options+0x1196/0x2180 net/dccp/feat.c:1416 [<00000000b1f6d94a>] dccp_parse_options+0xa2a/0x1260 net/dccp/options.c:125 [<0000000030d7b621>] dccp_rcv_state_process+0x197/0x13d0 net/dccp/input.c:650 [<000000001f74c72e>] dccp_v4_do_rcv+0xf9/0x1a0 net/dccp/ipv4.c:688 [<00000000a6c24128>] sk_backlog_rcv include/net/sock.h:1041 [inline] [<00000000a6c24128>] __release_sock+0x139/0x3b0 net/core/sock.c:2570 [<00000000cf1f3a53>] release_sock+0x54/0x1b0 net/core/sock.c:3111 [<000000008422fa23>] inet_wait_for_connect net/ipv4/af_inet.c:603 [inline] [<000000008422fa23>] __inet_stream_connect+0x5d0/0xf70 net/ipv4/af_inet.c:696 [<0000000015b6f64d>] inet_stream_connect+0x53/0xa0 net/ipv4/af_inet.c:735 [<0000000010122488>] __sys_connect_file+0x15c/0x1a0 net/socket.c:1865 [<00000000b4b70023>] __sys_connect+0x165/0x1a0 net/socket.c:1882 [<00000000f4cb3815>] __do_sys_connect net/socket.c:1892 [inline] [<00000000f4cb3815>] __se_sys_connect net/socket.c:1889 [inline] [<00000000f4cb3815>] __x64_sys_connect+0x6e/0xb0 net/socket.c:1889 [<00000000e7b1e839>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 [<0000000055e91434>] entry_SYSCALL_64_after_hwframe+0x67/0xd1 Clean up the allocated memory in case of dccp_feat_push_confirm() failure and bail out with an error reset code. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Affected packages

Ecosystem Package Introduced Fixed
Debian:11 linux 0 No fix
Debian:11 linux 0 5.10.234-1
Debian:11 linux-6.1 0 6.1.128-1~deb11u1
Debian:11 linux-6.1 0 6.1.6.1.128-1~deb11u1
Debian:12 linux 0 6.1.123-1
Debian:13 linux 0 6.12.5-1
Linux Kernel 2.6.29 5.4.287
Mageia:9 dwarves 0 1.29-1.mga9
Mageia:9 kernel 0 6.6.74-1.mga9
Mageia:9 kernel-linus 0 6.6.74-1.mga9
Mageia:9 kmod-virtualbox 0 7.0.24-64.mga9
Mageia:9 kmod-xtables-addons 0 3.24-70.mga9
SUSE:Linux Enterprise High Availability Extension 15 SP6 kernel-default 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Live Patching 12 SP5 kernel-default 0 4.12.14-122.247.1
SUSE:Linux Enterprise Live Patching 12 SP5 kgraft-patch-SLE12-SP5_Update_65 0 1-8.3.1
SUSE:Linux Enterprise Live Patching 15 SP6 kernel-default 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Live Patching 15 SP6 kernel-livepatch-SLE15-SP6-RT_Update_8 0 1-150600.1.3.1
SUSE:Linux Enterprise Live Patching 15 SP6 kernel-livepatch-SLE15-SP6_Update_8 0 1-150600.13.3.2
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-64kb 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-default 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-default-base 0 6.4.0-150600.23.38.1.150600.12.16.2
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-source 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-zfcpdump 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-coco 0 6.4.0-15061.12.coco15sp6.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-coco_debug 0 6.4.0-15061.12.coco15sp6.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-source-coco 0 6.4.0-15061.12.coco15sp6.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-syms-coco 0 6.4.0-15061.12.coco15sp6.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-docs 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-obs-build 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-source 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-syms 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Legacy 15 SP6 kernel-default 0 6.4.0-150600.23.38.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP6 kernel-azure 0 6.4.0-150600.8.26.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP6 kernel-source-azure 0 6.4.0-150600.8.26.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP6 kernel-syms-azure 0 6.4.0-150600.8.26.1
SUSE:Linux Enterprise Server 12 SP5-LTSS kernel-default 0 4.12.14-122.247.1
SUSE:Linux Enterprise Server 12 SP5-LTSS kernel-source 0 4.12.14-122.247.1
SUSE:Linux Enterprise Server 12 SP5-LTSS kernel-syms 0 4.12.14-122.247.1
SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-default 0 4.12.14-122.247.1
SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-source 0 4.12.14-122.247.1
SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5 kernel-syms 0 4.12.14-122.247.1
SUSE:Linux Enterprise Workstation Extension 15 SP6 kernel-default 0 6.4.0-150600.23.38.1
SUSE:Real Time Module 15 SP6 kernel-rt 0 6.4.0-150600.10.26.1
SUSE:Real Time Module 15 SP6 kernel-rt_debug 0 6.4.0-150600.10.26.1
SUSE:Real Time Module 15 SP6 kernel-source-rt 0 6.4.0-150600.10.26.1
SUSE:Real Time Module 15 SP6 kernel-syms-rt 0 6.4.0-150600.10.26.1
Ubuntu:16.04:LTS linux-hwe-edge 0 No fix
Ubuntu:18.04:LTS linux-aws-5.0 0 No fix
Ubuntu:18.04:LTS linux-aws-5.3 0 No fix
Ubuntu:18.04:LTS linux-azure 0 No fix
Ubuntu:18.04:LTS linux-azure-5.3 0 No fix
Ubuntu:18.04:LTS linux-azure-edge 0 No fix
Ubuntu:18.04:LTS linux-gcp 0 No fix
Ubuntu:18.04:LTS linux-gcp-5.3 0 No fix
Ubuntu:18.04:LTS linux-gke-4.15 0 No fix
Ubuntu:18.04:LTS linux-gke-5.4 0 No fix
Ubuntu:18.04:LTS linux-gkeop-5.4 0 No fix
Ubuntu:18.04:LTS linux-hwe 0 No fix
Ubuntu:18.04:LTS linux-hwe-edge 0 No fix
Ubuntu:18.04:LTS linux-oem 0 No fix
Ubuntu:18.04:LTS linux-oracle-5.0 0 No fix
Ubuntu:18.04:LTS linux-oracle-5.3 0 No fix
Ubuntu:20.04:LTS linux 0 No fix
Ubuntu:20.04:LTS linux 0 5.4.0-211.231
Ubuntu:20.04:LTS linux-aws 0 No fix
Ubuntu:20.04:LTS linux-aws 0 5.4.0-1142.152
Ubuntu:20.04:LTS linux-aws-5.11 0 No fix
Ubuntu:20.04:LTS linux-aws-5.13 0 No fix
Ubuntu:20.04:LTS linux-aws-5.15 0 No fix
Ubuntu:20.04:LTS linux-aws-5.15 0 5.15.0-1080.87~20.04.1
Ubuntu:20.04:LTS linux-aws-5.8 0 No fix
Ubuntu:20.04:LTS linux-azure 0 No fix
Ubuntu:20.04:LTS linux-azure 0 5.4.0-1147.154
Ubuntu:20.04:LTS linux-azure-5.11 0 No fix
Ubuntu:20.04:LTS linux-azure-5.13 0 No fix
Ubuntu:20.04:LTS linux-azure-5.15 0 No fix
Ubuntu:20.04:LTS linux-azure-5.15 0 5.15.0-1086.95~20.04.1
Ubuntu:20.04:LTS linux-azure-5.8 0 No fix
Ubuntu:20.04:LTS linux-azure-fde 0 No fix
Ubuntu:20.04:LTS linux-azure-fde-5.15 0 No fix
Ubuntu:20.04:LTS linux-bluefield 0 No fix
Ubuntu:20.04:LTS linux-bluefield 0 5.4.0-1101.108
Ubuntu:20.04:LTS linux-gcp 0 No fix
Ubuntu:20.04:LTS linux-gcp 0 5.4.0-1145.154
Ubuntu:20.04:LTS linux-gcp-5.11 0 No fix
Ubuntu:20.04:LTS linux-gcp-5.13 0 No fix
Ubuntu:20.04:LTS linux-gcp-5.15 0 No fix
Ubuntu:20.04:LTS linux-gcp-5.15 0 5.15.0-1081.90~20.04.1
Ubuntu:20.04:LTS linux-gcp-5.8 0 No fix
Ubuntu:20.04:LTS linux-gke 0 No fix
Ubuntu:20.04:LTS linux-gke-5.15 0 No fix
Ubuntu:20.04:LTS linux-gkeop 0 No fix
Ubuntu:20.04:LTS linux-gkeop-5.15 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.11 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.13 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.15 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.15 0 5.15.0-136.147~20.04.1
Ubuntu:20.04:LTS linux-hwe-5.8 0 No fix
Ubuntu:20.04:LTS linux-ibm 0 No fix
Ubuntu:20.04:LTS linux-ibm 0 5.4.0-1088.93
Ubuntu:20.04:LTS linux-ibm-5.15 0 No fix
Ubuntu:20.04:LTS linux-ibm-5.15 0 5.15.0-1074.77~20.04.1
Ubuntu:20.04:LTS linux-intel-5.13 0 No fix
Ubuntu:20.04:LTS linux-intel-iotg-5.15 0 No fix
Ubuntu:20.04:LTS linux-intel-iotg-5.15 0 5.15.0-1077.83~20.04.1
Ubuntu:20.04:LTS linux-iot 0 No fix
Ubuntu:20.04:LTS linux-iot 0 5.4.0-1048.51
Ubuntu:20.04:LTS linux-kvm 0 No fix
Ubuntu:20.04:LTS linux-kvm 0 5.4.0-1129.138
Ubuntu:20.04:LTS linux-lowlatency-hwe-5.15 0 No fix
Ubuntu:20.04:LTS linux-lowlatency-hwe-5.15 0 5.15.0-135.146~20.04.1
Ubuntu:20.04:LTS linux-oem-5.10 0 No fix
Ubuntu:20.04:LTS linux-oem-5.13 0 No fix
Ubuntu:20.04:LTS linux-oem-5.14 0 No fix
Ubuntu:20.04:LTS linux-oem-5.6 0 No fix
Ubuntu:20.04:LTS linux-oracle 0 No fix
Ubuntu:20.04:LTS linux-oracle 0 5.4.0-1140.150
Ubuntu:20.04:LTS linux-oracle-5.11 0 No fix
Ubuntu:20.04:LTS linux-oracle-5.13 0 No fix
Ubuntu:20.04:LTS linux-oracle-5.15 0 No fix
Ubuntu:20.04:LTS linux-oracle-5.15 0 5.15.0-1077.83~20.04.1
Ubuntu:20.04:LTS linux-oracle-5.8 0 No fix
Ubuntu:20.04:LTS linux-raspi 0 No fix
Ubuntu:20.04:LTS linux-raspi 0 5.4.0-1129.142
Ubuntu:20.04:LTS linux-raspi2 0 No fix
Ubuntu:20.04:LTS linux-riscv 0 No fix
Ubuntu:20.04:LTS linux-riscv-5.11 0 No fix
Ubuntu:20.04:LTS linux-riscv-5.15 0 No fix
Ubuntu:20.04:LTS linux-riscv-5.15 0 5.15.0-1075.79~20.04.1
Ubuntu:20.04:LTS linux-riscv-5.8 0 No fix
Ubuntu:20.04:LTS linux-xilinx-zynqmp 0 No fix
Ubuntu:20.04:LTS linux-xilinx-zynqmp 0 5.4.0-1060.64
Ubuntu:22.04:LTS linux 0 No fix
Ubuntu:22.04:LTS linux 0 5.15.0-135.146
Ubuntu:22.04:LTS linux-allwinner-5.19 0 No fix
Ubuntu:22.04:LTS linux-aws 0 No fix
Ubuntu:22.04:LTS linux-aws 0 5.15.0-1080.87
Ubuntu:22.04:LTS linux-aws-5.19 0 No fix
Ubuntu:22.04:LTS linux-aws-6.2 0 No fix
Ubuntu:22.04:LTS linux-aws-6.5 0 No fix
Ubuntu:22.04:LTS linux-aws-6.8 0 No fix
Ubuntu:22.04:LTS linux-aws-6.8 0 6.8.0-1027.29~22.04.1
Ubuntu:22.04:LTS linux-azure 0 No fix
Ubuntu:22.04:LTS linux-azure 0 5.15.0-1084.93
Ubuntu:22.04:LTS linux-azure-5.19 0 No fix
Ubuntu:22.04:LTS linux-azure-6.2 0 No fix
Ubuntu:22.04:LTS linux-azure-6.5 0 No fix
Ubuntu:22.04:LTS linux-azure-6.8 0 No fix
Ubuntu:22.04:LTS linux-azure-6.8 0 6.8.0-1027.32~22.04.1
Ubuntu:22.04:LTS linux-azure-fde 0 No fix
Ubuntu:22.04:LTS linux-azure-fde-5.19 0 No fix
Ubuntu:22.04:LTS linux-azure-fde-6.2 0 No fix
Ubuntu:22.04:LTS linux-gcp 0 No fix
Ubuntu:22.04:LTS linux-gcp 0 5.15.0-1079.88
Ubuntu:22.04:LTS linux-gcp-5.19 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.2 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.5 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.8 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.8 0 6.8.0-1028.30~22.04.1
Ubuntu:22.04:LTS linux-gke 0 No fix
Ubuntu:22.04:LTS linux-gke 0 5.15.0-1077.83
Ubuntu:22.04:LTS linux-gkeop 0 No fix
Ubuntu:22.04:LTS linux-gkeop 0 5.15.0-1062.70
Ubuntu:22.04:LTS linux-hwe-5.19 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.2 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.5 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.8 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.8 0 6.8.0-58.60~22.04.1
Ubuntu:22.04:LTS linux-ibm 0 No fix
Ubuntu:22.04:LTS linux-ibm 0 5.15.0-1072.75
Ubuntu:22.04:LTS linux-ibm-6.8 0 6.8.0-1024.24~22.04.1
Ubuntu:22.04:LTS linux-intel-iot-realtime 0 No fix
Ubuntu:22.04:LTS linux-intel-iot-realtime 0 5.15.0-1073.75
Ubuntu:22.04:LTS linux-intel-iotg 0 No fix
Ubuntu:22.04:LTS linux-intel-iotg 0 5.15.0-1075.81
Ubuntu:22.04:LTS linux-kvm 0 No fix
Ubuntu:22.04:LTS linux-kvm 0 5.15.0-1076.81
Ubuntu:22.04:LTS linux-lowlatency 0 No fix
Ubuntu:22.04:LTS linux-lowlatency 0 5.15.0-135.146
Ubuntu:22.04:LTS linux-lowlatency-hwe-5.19 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.2 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.5 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.8 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.8 0 6.8.0-58.60.1~22.04.1
Ubuntu:22.04:LTS linux-nvidia 0 No fix
Ubuntu:22.04:LTS linux-nvidia 0 5.15.0-1074.75
Ubuntu:22.04:LTS linux-nvidia-6.2 0 No fix
Ubuntu:22.04:LTS linux-nvidia-6.5 0 No fix
Ubuntu:22.04:LTS linux-nvidia-6.8 0 No fix
Ubuntu:22.04:LTS linux-nvidia-6.8 0 6.8.0-1026.29~22.04.1
Ubuntu:22.04:LTS linux-nvidia-tegra 0 5.15.0-1033.33
Ubuntu:22.04:LTS linux-nvidia-tegra-igx 0 5.15.0-1021.21
Ubuntu:22.04:LTS linux-oem-5.17 0 No fix
Ubuntu:22.04:LTS linux-oem-6.0 0 No fix
Ubuntu:22.04:LTS linux-oem-6.1 0 No fix
Ubuntu:22.04:LTS linux-oem-6.5 0 No fix
Ubuntu:22.04:LTS linux-oracle 0 No fix
Ubuntu:22.04:LTS linux-oracle 0 5.15.0-1077.83
Ubuntu:22.04:LTS linux-oracle-6.5 0 No fix
Ubuntu:22.04:LTS linux-oracle-6.8 0 No fix

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