UBUNTU-CVE-2025-21891: Medium severity ubuntu/linux-aws vulnerability

Q: Which systems are exposed to this issue?

The affected software list includes Ubuntu linux, linux-aws, linux-azure, linux-gcp, and their listed FIPS variants. Exposure is relevant where the kernel's ipvlan functionality processes outbound IPv4 or IPv6 traffic.

Q: What access would an attacker need?

The supplied severity vector indicates local attack access and low privileges are required. No user interaction is required.

Q: What is the expected impact?

The severity vector indicates low availability impact, with no reported impact on confidentiality or integrity. The flaw involves handling network headers that may not be present in the linear portion of an skb.

Q: What does the fix change?

The resolution adds pskb_network_may_pull() checks to both IPv4 and IPv6 ipvlan handlers, ensuring required network headers are available in the skb linear data before they are accessed.

Published Mar 27, 2025

Updated

In the Linux kernel, the following vulnerability has been resolved: ipvlan: ensure network headers are in skb linear part syzbot found that ipvlanprocessv6outbound() was assuming the IPv6 network header isis present in skb->head [1] Add the needed pskbnetworkmaypull() calls for both IPv4 and IPv6 handlers. [1] BUG: KMSAN: uninit-value in ipv6addrtype+0xa2/0x490 net/ipv6/addrconfcore.c:47 ipv6addrtype+0xa2/0x490 net/ipv6/addrconfcore.c:47 ipv6addrtype include/net/ipv6.h:555 [inline] ip6routeoutputflagsnoref net/ipv6/route.c:2616 [inline] ip6routeoutputflags+0x51/0x720 net/ipv6/route.c:2651 ip6routeoutput include/net/ip6route.h:93 [inline] ipvlanroutev6outbound+0x24e/0x520 drivers/net/ipvlan/ipvlancore.c:476 ipvlanprocessv6outbound drivers/net/ipvlan/ipvlancore.c:491 [inline] ipvlanprocessoutbound drivers/net/ipvlan/ipvlancore.c:541 [inline] ipvlanxmitmodel3 drivers/net/ipvlan/ipvlancore.c:605 [inline] ipvlanqueuexmit+0xd72/0x1780 drivers/net/ipvlan/ipvlancore.c:671 ipvlanstartxmit+0x5b/0x210 drivers/net/ipvlan/ipvlanmain.c:223 netdevstartxmit include/linux/netdevice.h:5150 [inline] netdevstartxmit include/linux/netdevice.h:5159 [inline] xmitone net/core/dev.c:3735 [inline] devhardstartxmit+0x247/0xa20 net/core/dev.c:3751 schdirectxmit+0x399/0xd40 net/sched/schgeneric.c:343 qdiscrestart net/sched/schgeneric.c:408 [inline] qdiscrun+0x14da/0x35d0 net/sched/schgeneric.c:416 qdiscrun+0x141/0x4d0 include/net/pktsched.h:127 nettxaction+0x78b/0x940 net/core/dev.c:5484 handlesoftirqs+0x1a0/0x7c0 kernel/softirq.c:561 dosoftirq+0x14/0x1a kernel/softirq.c:595 dosoftirq+0x9a/0x100 kernel/softirq.c:462 localbhenableip+0x9f/0xb0 kernel/softirq.c:389 localbhenable include/linux/bottomhalf.h:33 [inline] rcureadunlockbh include/linux/rcupdate.h:919 [inline] devqueuexmit+0x2758/0x57d0 net/core/dev.c:4611 devqueuexmit include/linux/netdevice.h:3311 [inline] packetxmit+0x9c/0x6c0 net/packet/afpacket.c:276 packetsnd net/packet/afpacket.c:3132 [inline] packetsendmsg+0x93e0/0xa7e0 net/packet/afpacket.c:3164 socksendmsgnosec net/socket.c:718 [inline]

Affected Software

212 affected componentsFixes available

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*

ubuntu/linux-azure*

ubuntu/linux-azure-4.15*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-5.4*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-4.15*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gcp-5.4*

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-5.4*

ubuntu/linux-hwe-edge*

ubuntu/linux-ibm-5.4*

ubuntu/linux-kvm*

ubuntu/linux-oem*

ubuntu/linux-oracle*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-oracle-5.4*

ubuntu/linux-raspi-5.4*

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*

ubuntu/linux-aws*

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.15*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.15*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-azure-fde-5.15*

ubuntu/linux-bluefield*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15*

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*

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm*

ubuntu/linux-ibm-5.15*

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15*

ubuntu/linux-iot*

ubuntu/linux-kvm*

ubuntu/linux-lowlatency-hwe-5.15*

ubuntu/linux-nvidia-tegra-5.15*

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.15*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15*

ubuntu/linux-riscv-5.8*

ubuntu/linux-xilinx-zynqmp*

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*

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws*

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*

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*

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp*

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*

ubuntu/linux-gkeop*

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*

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*

ubuntu/linux-kvm*

ubuntu/linux-lowlatency*

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*

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*

ubuntu/linux-nvidia-tegra-igx*

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle*

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*

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*

ubuntu/linux-bluefield*

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-realtime*

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*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

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<6.11.0-1015.15~24.04.1

6.11.0-1015.15~24.04.1

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<6.11.0-1015.15~24.04.1

6.11.0-1015.15~24.04.1

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<6.11.0-26.26~24.04.1

6.11.0-26.26~24.04.1

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<6.11.0-1014.15~24.04.1

6.11.0-1014.15~24.04.1

ubuntu/linux-nvidia<6.8.0-1039.42

6.8.0-1039.42

ubuntu/linux-nvidia-6.11<6.11.0-1010.10

6.11.0-1010.10

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<6.11.0-1022.22

6.11.0-1022.22

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-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1036.42~22.04.1
Upgrade
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-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-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.37~22.04.1
Upgrade
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-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42~22.04.1
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-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84~22.04.1
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1034.35~22.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1038.44
Upgrade
Upgrade ubuntu/linux-azure-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1015.15~24.04.1
Upgrade
Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1025.27
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.42
Upgrade
Upgrade ubuntu/linux-gcp-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1015.15~24.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1036.40
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.25
Upgrade
Upgrade ubuntu/linux-hwe-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-26.26~24.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.37
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1014.15~24.04.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42
Upgrade
Upgrade ubuntu/linux-nvidia-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1010.10
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.42.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 6.8.0-1010.10
Upgrade
Upgrade ubuntu/linux-oem-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1022.22
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1037.38
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.43
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1018.19
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2030.31
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1034.35
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1039.41+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.46+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-84.84+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-1040.42+fips1
Compensating control
In the ipvlan IPv4 and IPv6 outbound handlers, add the required pskb_network_may_pull() calls to ensure network headers are present in the skb linear part before accessing them.

Event History

Mar 27, 2025

CVE Published

via OSV·03:15 PM

Data Sourced

via OSV·03:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which systems are exposed to this issue?

The affected software list includes Ubuntu linux, linux-aws, linux-azure, linux-gcp, and their listed FIPS variants. Exposure is relevant where the kernel's ipvlan functionality processes outbound IPv4 or IPv6 traffic.

What access would an attacker need?

The supplied severity vector indicates local attack access and low privileges are required. No user interaction is required.

What is the expected impact?

The severity vector indicates low availability impact, with no reported impact on confidentiality or integrity. The flaw involves handling network headers that may not be present in the linear portion of an skb.

What does the fix change?

The resolution adds pskb_network_may_pull() checks to both IPv4 and IPv6 ipvlan handlers, ensuring required network headers are available in the skb linear data before they are accessed.

UBUNTU-CVE-2025-21891: Medium severity ubuntu/linux-aws vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Which systems are exposed to this issue?

What access would an attacker need?

What is the expected impact?

What does the fix change?

Company

Resources

Contact

Frequently Asked Questions

Which systems are exposed to this issue?

What access would an attacker need?

What is the expected impact?

What does the fix change?