UBUNTU-CVE-2025-21922: Medium severity ubuntu/linux vulnerability

Q: What conditions are required to trigger this issue?

The affected system needs to use the Linux kernel PPP driver with a socket filter/BPF program that accesses the PPP header. The reported case involves a filter that skips two bytes, reads the PPP Protocol field, and reads the direction byte.

Q: What information could be exposed?

The issue is an uninitialized-value condition: the PPP driver initializes the first header byte indicating direction but does not initialize the second byte. A socket filter that reads that header can trigger a KMSAN uninitialized-value warning.

Q: Who can exploit this vulnerability?

The supplied vector requires local access and low privileges, with no user interaction. The available data does not establish remote exploitability or impact on confidentiality, integrity, or availability beyond the reported uninitialized-value condition.

Published Apr 1, 2025

Updated

In the Linux kernel, the following vulnerability has been resolved: ppp: Fix KMSAN uninit-value warning with bpf Syzbot caught an "KMSAN: uninit-value" warning [1], which is caused by the ppp driver not initializing a 2-byte header when using socket filter. The following code can generate a PPP filter BPF program: ''' struct bpfprogram fp; pcapt handle; handle = pcapopendead(DLTPPPPPPD, 65535); pcapcompile(handle, &fp, "ip and outbound", 0, 0); bpfdump(&fp, 1); ''' Its output is: ''' (000) ldh [2] (001) jeq #0x21 jt 2 jf 5 (002) ldb [0] (003) jeq #0x1 jt 4 jf 5 (004) ret #65535 (005) ret #0 ''' Wen can find similar code at the following link: https://github.com/ppp-project/ppp/blob/master/pppd/options.c#L1680 The maintainer of this code repository is also the original maintainer of the ppp driver. As you can see the BPF program skips 2 bytes of data and then reads the 'Protocol' field to determine if it's an IP packet. Then it read the first byte of the first 2 bytes to determine the direction. The issue is that only the first byte indicating direction is initialized in current ppp driver code while the second byte is not initialized. For normal BPF programs generated by libpcap, uninitialized data won't be used, so it's not a problem. However, for carefully crafted BPF programs, such as those generated by syzkaller [2], which start reading from offset 0, the uninitialized data will be used and caught by KMSAN. [1] https://syzkaller.appspot.com/bug?extid=853242d9c9917165d791 [2] https://syzkaller.appspot.com/text?tag=ReproC&x=11994913980000

Affected Software

212 affected componentsFixes available

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-azure*

ubuntu/linux-lts-xenial*

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-aws-hwe*

ubuntu/linux-azure*

ubuntu/linux-gcp*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-kvm*

ubuntu/linux-oracle*

ubuntu/linux-fips*

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-aws-5.4<5.4.0-1146.156~18.04.1

5.4.0-1146.156~18.04.1

ubuntu/linux-azure*

ubuntu/linux-azure-4.15*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-5.4<5.4.0-1151.158~18.04.1

5.4.0-1151.158~18.04.1

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-4.15*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gcp-5.4<5.4.0-1149.158~18.04.1

5.4.0-1149.158~18.04.1

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-5.4<5.4.0-216.236~18.04.1

5.4.0-216.236~18.04.1

ubuntu/linux-hwe-edge*

ubuntu/linux-ibm-5.4<5.4.0-1092.97~18.04.1

5.4.0-1092.97~18.04.1

ubuntu/linux-kvm*

ubuntu/linux-oem*

ubuntu/linux-oracle*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-oracle-5.4<5.4.0-1144.154~18.04.1

5.4.0-1144.154~18.04.1

ubuntu/linux-raspi-5.4<5.4.0-1129.142~18.04.1

5.4.0-1129.142~18.04.1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux<5.4.0-216.236

5.4.0-216.236

ubuntu/linux-aws<5.4.0-1146.156

5.4.0-1146.156

ubuntu/linux-aws-5.15<5.15.0-1084.91~20.04.1

5.15.0-1084.91~20.04.1

ubuntu/linux-azure<5.4.0-1151.158

5.4.0-1151.158

ubuntu/linux-azure-5.15<5.15.0-1089.98~20.04.1

5.15.0-1089.98~20.04.1

ubuntu/linux-bluefield<5.4.0-1105.112

5.4.0-1105.112

ubuntu/linux-gcp<5.4.0-1149.158

5.4.0-1149.158

ubuntu/linux-gcp-5.15<5.15.0-1083.92~20.04.1

5.15.0-1083.92~20.04.1

ubuntu/linux-ibm<5.4.0-1092.97

5.4.0-1092.97

ubuntu/linux-ibm-5.15<5.15.0-1076.79~20.04.1

5.15.0-1076.79~20.04.1

ubuntu/linux-intel-iotg-5.15<5.15.0-1079.85~20.04.1

5.15.0-1079.85~20.04.1

ubuntu/linux-kvm<5.4.0-1133.142

5.4.0-1133.142

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-140.150~20.04.1

5.15.0-140.150~20.04.1

ubuntu/linux-oracle<5.4.0-1144.154

5.4.0-1144.154

ubuntu/linux-oracle-5.15<5.15.0-1081.87~20.04.1

5.15.0-1081.87~20.04.1

ubuntu/linux-raspi<5.4.0-1129.142

5.4.0-1129.142

ubuntu/linux-riscv-5.15<5.15.0-1079.83~20.04.1

5.15.0-1079.83~20.04.1

ubuntu/linux-xilinx-zynqmp<5.4.0-1064.68

5.4.0-1064.68

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.8*

ubuntu/linux-gke*

ubuntu/linux-gke-5.15*

ubuntu/linux-gkeop*

ubuntu/linux-gkeop-5.15*

ubuntu/linux-hwe-5.11*

ubuntu/linux-hwe-5.13*

ubuntu/linux-hwe-5.15<5.15.0-142.152~20.04.1

5.15.0-142.152~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-intel-5.13*

ubuntu/linux-iot<5.4.0-1051.54

5.4.0-1051.54

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1039.39~20.04.1

5.15.0-1039.39~20.04.1

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.8*

ubuntu/linux-aws-fips<5.4.0-1146.156+fips1

5.4.0-1146.156+fips1

ubuntu/linux-azure-fips<5.4.0-1151.158+fips1

5.4.0-1151.158+fips1

ubuntu/linux-fips<5.4.0-1120.130

5.4.0-1120.130

ubuntu/linux-gcp-fips<5.4.0-1149.158+fips1

5.4.0-1149.158+fips1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux<5.15.0-140.150

5.15.0-140.150

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1084.91

5.15.0-1084.91

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1039.41~22.04.1

6.8.0-1039.41~22.04.1

ubuntu/linux-azure<5.15.0-1089.98

5.15.0-1089.98

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1036.42~22.04.1

6.8.0-1036.42~22.04.1

ubuntu/linux-azure-fde<5.15.0-1089.98.1

5.15.0-1089.98.1

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp<5.15.0-1083.92

5.15.0-1083.92

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8<6.8.0-1040.42~22.04.1

6.8.0-1040.42~22.04.1

ubuntu/linux-gke<5.15.0-1081.87

5.15.0-1081.87

ubuntu/linux-gkeop<5.15.0-1066.74

5.15.0-1066.74

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-85.85~22.04.1

6.8.0-85.85~22.04.1

ubuntu/linux-ibm<5.15.0-1076.79

5.15.0-1076.79

ubuntu/linux-ibm-6.8<6.8.0-1037.37~22.04.1

6.8.0-1037.37~22.04.1

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-intel-iotg<5.15.0-1079.85

5.15.0-1079.85

ubuntu/linux-kvm<5.15.0-1080.85

5.15.0-1080.85

ubuntu/linux-lowlatency<5.15.0-140.150

5.15.0-140.150

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-84.84.1~22.04.1

6.8.0-84.84.1~22.04.1

ubuntu/linux-nvidia<5.15.0-1078.79

5.15.0-1078.79

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1039.42~22.04.1

6.8.0-1039.42~22.04.1

ubuntu/linux-nvidia-tegra<5.15.0-1037.37

5.15.0-1037.37

ubuntu/linux-nvidia-tegra-igx<5.15.0-1026.26

5.15.0-1026.26

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1081.87

5.15.0-1081.87

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1037.38~22.04.1

6.8.0-1037.38~22.04.1

ubuntu/linux-raspi<5.15.0-1078.81

5.15.0-1078.81

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-84.84~22.04.1

6.8.0-84.84~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp<5.15.0-1050.54

5.15.0-1050.54

ubuntu/linux-bluefield<5.15.0-1066.68

5.15.0-1066.68

ubuntu/linux-intel-iot-realtime<5.15.0-1077.79

5.15.0-1077.79

ubuntu/linux-realtime<5.15.0-1084.93

5.15.0-1084.93

ubuntu/linux-realtime-6.8<6.8.1-1034.35~22.04.1

6.8.1-1034.35~22.04.1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-aws-fips<5.15.0-1084.91+fips1

5.15.0-1084.91+fips1

ubuntu/linux-azure-fips<5.15.0-1089.98+fips1

5.15.0-1089.98+fips1

ubuntu/linux-fips<5.15.0-140.150+fips1

5.15.0-140.150+fips1

ubuntu/linux-gcp-fips<5.15.0-1083.92+fips1

5.15.0-1083.92+fips1

ubuntu/linux<6.8.0-84.84

6.8.0-84.84

ubuntu/linux-aws<6.8.0-1039.41

6.8.0-1039.41

ubuntu/linux-azure<6.8.0-1038.44

6.8.0-1038.44

ubuntu/linux-azure-6.11<6.11.0-1018.18~24.04.1

6.11.0-1018.18~24.04.1

ubuntu/linux-azure-nvidia<6.8.0-1025.27

6.8.0-1025.27

ubuntu/linux-gcp<6.8.0-1040.42

6.8.0-1040.42

ubuntu/linux-gcp-6.11<6.11.0-1016.16~24.04.1

6.11.0-1016.16~24.04.1

ubuntu/linux-gke<6.8.0-1036.40

6.8.0-1036.40

ubuntu/linux-gkeop<6.8.0-1023.25

6.8.0-1023.25

ubuntu/linux-hwe-6.11<6.11.0-28.28~24.04.1

6.11.0-28.28~24.04.1

ubuntu/linux-ibm<6.8.0-1037.37

6.8.0-1037.37

ubuntu/linux-intel*

ubuntu/linux-lowlatency<6.8.0-84.84.1

6.8.0-84.84.1

ubuntu/linux-lowlatency-hwe-6.11<6.11.0-1015.16~24.04.2

6.11.0-1015.16~24.04.2

ubuntu/linux-nvidia<6.8.0-1039.42

6.8.0-1039.42

ubuntu/linux-nvidia-6.11<6.11.0-1012.12

6.11.0-1012.12

ubuntu/linux-nvidia-lowlatency<6.8.0-1039.42.1

6.8.0-1039.42.1

ubuntu/linux-nvidia-tegra<6.8.0-1010.10

6.8.0-1010.10

ubuntu/linux-oem-6.11<6.11.0-1024.24

6.11.0-1024.24

ubuntu/linux-oem-6.8*

ubuntu/linux-oracle<6.8.0-1037.38

6.8.0-1037.38

ubuntu/linux-raspi<6.8.0-1039.43

6.8.0-1039.43

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-xilinx<6.8.0-1018.19

6.8.0-1018.19

ubuntu/linux-raspi-realtime<6.8.0-2030.31

6.8.0-2030.31

ubuntu/linux-realtime<6.8.1-1034.35

6.8.1-1034.35

ubuntu/linux-aws-fips<6.8.0-1039.41+fips1

6.8.0-1039.41+fips1

ubuntu/linux-azure-fips<6.8.0-1040.46+fips1

6.8.0-1040.46+fips1

ubuntu/linux-fips<6.8.0-84.84+fips1

6.8.0-84.84+fips1

ubuntu/linux-gcp-fips<6.8.0-1040.42+fips1

6.8.0-1040.42+fips1

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1146.156~18.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1151.158~18.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1149.158~18.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-216.236~18.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1092.97~18.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1144.154~18.04.1
Upgrade
Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1129.142~18.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.4.0-216.236
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.4.0-1146.156
Upgrade
Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1084.91~20.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.4.0-1151.158
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1089.98~20.04.1
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.4.0-1105.112
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.4.0-1149.158
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.92~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.4.0-1092.97
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1076.79~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1079.85~20.04.1
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.4.0-1133.142
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-140.150~20.04.1
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Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.4.0-1144.154
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Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1081.87~20.04.1
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Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.4.0-1129.142
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Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1079.83~20.04.1
Upgrade
Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.
Fixed in 5.4.0-1064.68
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-142.152~20.04.1
Upgrade
Upgrade ubuntu/linux-iot to a version that resolves this vulnerability.
Fixed in 5.4.0-1051.54
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1039.39~20.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1146.156+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1151.158+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1120.130
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1149.158+fips1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-140.150
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1084.91
Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41~22.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1089.98
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Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1036.42~22.04.1
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Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1089.98.1
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Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.92
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Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.42~22.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1081.87
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1066.74
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-85.85~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1076.79
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.37~22.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1079.85
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1080.85
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Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-140.150
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Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1078.79
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42~22.04.1
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Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1037.37
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Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1026.26
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Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1081.87
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.38~22.04.1
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.15.0-1078.81
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84~22.04.1
Upgrade
Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.
Fixed in 5.15.0-1050.54
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Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1066.68
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1077.79
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1084.93
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1034.35~22.04.1
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Fixed in 5.15.0-1084.91+fips1
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Fixed in 5.15.0-1089.98+fips1
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Fixed in 5.15.0-140.150+fips1
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Fixed in 5.15.0-1083.92+fips1
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Fixed in 6.8.0-84.84
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Fixed in 6.8.0-1039.41
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Fixed in 6.8.0-1038.44
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Fixed in 6.11.0-1018.18~24.04.1
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Fixed in 6.8.0-1025.27
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Fixed in 6.8.0-1040.42
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Fixed in 6.11.0-1016.16~24.04.1
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Fixed in 6.8.0-1036.40
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Fixed in 6.8.0-1023.25
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Fixed in 6.11.0-28.28~24.04.1
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Fixed in 6.8.0-1037.37
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Fixed in 6.8.0-84.84.1
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Fixed in 6.11.0-1015.16~24.04.2
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Fixed in 6.8.0-1039.42
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Fixed in 6.11.0-1012.12
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Fixed in 6.8.0-1039.42.1
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Fixed in 6.8.0-1010.10
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Fixed in 6.11.0-1024.24
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Fixed in 6.8.0-1037.38
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Fixed in 6.8.0-1039.43
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Fixed in 6.8.0-1018.19
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Fixed in 6.8.0-2030.31
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Fixed in 6.8.1-1034.35
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Fixed in 6.8.0-1039.41+fips1
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Fixed in 6.8.0-1040.46+fips1
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Fixed in 6.8.0-84.84+fips1
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Fixed in 6.8.0-1040.42+fips1

Event History

Apr 1, 2025

CVE Published

via OSV·04:15 PM

Data Sourced

via OSV·04:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

What conditions are required to trigger this issue?

The affected system needs to use the Linux kernel PPP driver with a socket filter/BPF program that accesses the PPP header. The reported case involves a filter that skips two bytes, reads the PPP Protocol field, and reads the direction byte.

What information could be exposed?

The issue is an uninitialized-value condition: the PPP driver initializes the first header byte indicating direction but does not initialize the second byte. A socket filter that reads that header can trigger a KMSAN uninitialized-value warning.

Who can exploit this vulnerability?

The supplied vector requires local access and low privileges, with no user interaction. The available data does not establish remote exploitability or impact on confidentiality, integrity, or availability beyond the reported uninitialized-value condition.

UBUNTU-CVE-2025-21922: Medium severity ubuntu/linux vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

What conditions are required to trigger this issue?

What information could be exposed?

Who can exploit this vulnerability?

Company

Resources

Contact

Frequently Asked Questions

What conditions are required to trigger this issue?

What information could be exposed?

Who can exploit this vulnerability?