CVE-2025-38574: pptp: ensure minimal skb length in pptp_xmit()
In the Linux kernel, the following vulnerability has been resolved:
pptp: ensure minimal skb length in pptpxmit()
Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data on pppsynctxmung") fixed pppsynctxmunge()
We need a similar fix in pptpxmit(), otherwise we might read uninit data as reported by syzbot.
BUG: KMSAN: uninit-value in pptpxmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193 pptpxmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193 pppchannelbridgeinput drivers/net/ppp/pppgeneric.c:2290 [inline] pppinput+0x1d6/0xe60 drivers/net/ppp/pppgeneric.c:2314 pppoercvcore+0x1e8/0x760 drivers/net/ppp/pppoe.c:379 skbacklogrcv+0x142/0x420 include/net/sock.h:1148 releasesock+0x1d3/0x330 net/core/sock.c:3213 releasesock+0x6b/0x270 net/core/sock.c:3767 pppoesendmsg+0x15d/0xcb0 drivers/net/ppp/pppoe.c:904 socksendmsgnosec net/socket.c:712 [inline] socksendmsg+0x330/0x3d0 net/socket.c:727 syssendmsg+0x893/0xd80 net/socket.c:2566 syssendmsg+0x271/0x3b0 net/socket.c:2620 syssendmmsg+0x2d9/0x7c0 net/socket.c:2709
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
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ubuntu/linux-aws-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1097.104~20.04.1 - Upgrade
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ubuntu/linux-azure-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1102.111~20.04.1 - Upgrade
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ubuntu/linux-gcp-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1097.106~20.04.1 - Upgrade
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ubuntu/linux-hwe-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-163.173~20.04.1 - Upgrade
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ubuntu/linux-ibm-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1091.94~20.04.1 - Upgrade
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ubuntu/linux-intel-iotg-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1092.98~20.04.1 - Upgrade
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ubuntu/linux-lowlatency-hwe-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-163.173~20.04.1 - Upgrade
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ubuntu/linux-nvidia-tegra-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1049.49~20.04.1 - Upgrade
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ubuntu/linux-oracle-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1094.100~20.04.1 - Upgrade
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ubuntu/linux-riscv-5.15to a version that resolves this vulnerability.Fixed in 5.15.0-1092.96~20.04.1 - Upgrade
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ubuntu/linuxto a version that resolves this vulnerability.Fixed in 5.15.0-163.173 - Upgrade
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ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 5.15.0-1097.104 - Upgrade
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ubuntu/linux-aws-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1046.49~22.04.1 - Upgrade
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ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 5.15.0-1101.110 - Upgrade
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ubuntu/linux-azure-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1051.57~22.04.1 - Upgrade
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ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 5.15.0-1102.111.1 - Upgrade
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ubuntu/linux-azure-fde-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1046.53~22.04.1 - Upgrade
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ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 5.15.0-1097.106 - Upgrade
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ubuntu/linux-gcp-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1047.50~22.04.2 - Upgrade
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ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 5.15.0-1093.99 - Upgrade
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ubuntu/linux-gkeopto a version that resolves this vulnerability.Fixed in 5.15.0-1080.88 - Upgrade
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ubuntu/linux-hwe-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-100.100~22.04.1 - Upgrade
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ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 5.15.0-1091.94 - Upgrade
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ubuntu/linux-ibm-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1044.44~22.04.1 - Upgrade
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ubuntu/linux-intel-iotgto a version that resolves this vulnerability.Fixed in 5.15.0-1092.98 - Upgrade
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ubuntu/linux-kvmto a version that resolves this vulnerability.Fixed in 5.15.0-1089.94 - Upgrade
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ubuntu/linux-lowlatencyto a version that resolves this vulnerability.Fixed in 5.15.0-163.173 - Upgrade
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ubuntu/linux-lowlatency-hwe-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-100.100.1~22.04.1 - Upgrade
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ubuntu/linux-nvidiato a version that resolves this vulnerability.Fixed in 5.15.0-1092.93 - Upgrade
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ubuntu/linux-nvidia-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1046.49~22.04.1 - Upgrade
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ubuntu/linux-nvidia-tegrato a version that resolves this vulnerability.Fixed in 5.15.0-1049.49 - Upgrade
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ubuntu/linux-nvidia-tegra-igxto a version that resolves this vulnerability.Fixed in 5.15.0-1038.38 - Upgrade
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ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 5.15.0-1094.100 - Upgrade
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ubuntu/linux-oracle-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-1043.44~22.04.1 - Upgrade
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ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 5.15.0-1091.94 - Upgrade
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ubuntu/linux-riscv-6.8to a version that resolves this vulnerability.Fixed in 6.8.0-100.100~22.04.1 - Upgrade
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ubuntu/linux-xilinx-zynqmpto a version that resolves this vulnerability.Fixed in 5.15.0-1061.65 - Upgrade
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ubuntu/linux-bluefieldto a version that resolves this vulnerability.Fixed in 5.15.0-1081.83 - Upgrade
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ubuntu/linux-intel-iot-realtimeto a version that resolves this vulnerability.Fixed in 5.15.0-1089.91 - Upgrade
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ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 5.15.0-1096.105 - Upgrade
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ubuntu/linux-realtime-6.8to a version that resolves this vulnerability.Fixed in 6.8.1-1041.42~22.04.1 - Upgrade
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ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1097.104+fips1 - Upgrade
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ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1101.110+fips1 - Upgrade
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ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-163.173+fips1 - Upgrade
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ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 5.15.0-1097.106+fips1 - Upgrade
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ubuntu/linuxto a version that resolves this vulnerability.Fixed in 6.8.0-100.100 - Upgrade
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ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 6.8.0-1046.49 - Upgrade
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ubuntu/linux-aws-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-1017.17~24.04.1 - Upgrade
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ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 6.8.0-1046.52 - Upgrade
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ubuntu/linux-azure-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-1017.17~24.04.1 - Upgrade
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ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 6.8.0-1046.53 - Upgrade
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ubuntu/linux-azure-nvidiato a version that resolves this vulnerability.Fixed in 6.8.0-1039.42 - Upgrade
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ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 6.8.0-1047.50 - Upgrade
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ubuntu/linux-gcp-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-1020.21~24.04.1 - Upgrade
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ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 6.8.0-1043.48 - Upgrade
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ubuntu/linux-gkeopto a version that resolves this vulnerability.Fixed in 6.8.0-1030.33 - Upgrade
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ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 6.8.0-1044.44 - Upgrade
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ubuntu/linux-lowlatencyto a version that resolves this vulnerability.Fixed in 6.8.0-100.100.1 - Upgrade
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ubuntu/linux-nvidiato a version that resolves this vulnerability.Fixed in 6.8.0-1046.49 - Upgrade
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ubuntu/linux-nvidia-lowlatencyto a version that resolves this vulnerability.Fixed in 6.8.0-1046.49.1 - Upgrade
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ubuntu/linux-nvidia-tegrato a version that resolves this vulnerability.Fixed in 6.8.0-1020.20 - Upgrade
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ubuntu/linux-oem-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-1016.16 - Upgrade
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ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 6.8.0-1043.44 - Upgrade
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ubuntu/linux-oracle-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-1017.17~24.04.1 - Upgrade
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ubuntu/linux-raspito a version that resolves this vulnerability.Fixed in 6.8.0-1047.51 - Upgrade
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ubuntu/linux-riscv-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-36.36.1~24.04.1 - Upgrade
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ubuntu/linux-xilinxto a version that resolves this vulnerability.Fixed in 6.8.0-1023.24 - Upgrade
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ubuntu/linux-bluefieldto a version that resolves this vulnerability.Fixed in 6.8.0-1016.20 - Upgrade
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ubuntu/linux-raspi-realtimeto a version that resolves this vulnerability.Fixed in 6.8.0-2037.38 - Upgrade
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ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 6.8.1-1041.42 - Upgrade
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ubuntu/linux-realtime-6.14to a version that resolves this vulnerability.Fixed in 6.14.0-1016.16~24.04.1 - Upgrade
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ubuntu/linux-aws-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-1046.49+fips1 - Upgrade
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ubuntu/linux-azure-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-1046.52+fips1 - Upgrade
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ubuntu/linux-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-100.100+fips1 - Upgrade
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ubuntu/linux-gcp-fipsto a version that resolves this vulnerability.Fixed in 6.8.0-1047.50+fips1
Event History
Frequently Asked Questions
What is the severity of CVE-2025-38574?
CVE-2025-38574 is considered a medium severity vulnerability due to the potential for data corruption.
How do I fix CVE-2025-38574?
To fix CVE-2025-38574, update the Linux kernel to the latest version that includes the security patch.
What impact does CVE-2025-38574 have on affected systems?
CVE-2025-38574 may lead to instability and data integrity issues in systems utilizing the PPTP protocol.
Is CVE-2025-38574 exploitable remotely?
CVE-2025-38574 can potentially be exploited remotely if the PPTP service is exposed to untrusted networks.
When was CVE-2025-38574 first reported?
CVE-2025-38574 was first reported as resolved with the commit aabc6596ffb3 in the Linux kernel.