UBUNTU-CVE-2025-37964: High severity ubuntu/linux-hwe-edge vulnerability

Q: What level of access does an attacker need to exploit this issue?

The CVSS vector indicates local access and low privileges are required. User interaction is not required, but an additional attack condition must be present.

Q: Which Ubuntu kernel packages are listed as affected?

The listed packages are linux-azure-fde, linux-realtime, linux-hwe-edge, linux-azure, linux-gcp, linux-gke, linux-gkeop, and linux-riscv.

Q: What is the potential security impact within the affected system?

The CVSS vector rates confidentiality, integrity, and availability impact as high. The impact scope is unchanged, with no indicated impact on a separate security authority.

Published May 20, 2025

Updated

In the Linux kernel, the following vulnerability has been resolved: x86/mm: Eliminate window where TLB flushes may be inadvertently skipped tl;dr: There is a window in the mm switching code where the new CR3 is set and the CPU should be getting TLB flushes for the new mm. But shouldflushtlb() has a bug and suppresses the flush. Fix it by widening the window where shouldflushtlb() sends an IPI. Long Version: === History === There were a few things leading up to this. First, updating mmcpumask() was observed to be too expensive, so it was made lazier. But being lazy caused too many unnecessary IPIs to CPUs due to the now-lazy mmcpumask(). So code was added to cull mmcpumask() periodically[2]. But that culling was a bit too aggressive and skipped sending TLB flushes to CPUs that need them. So here we are again. === Problem === The too-aggressive code in shouldflushtlb() strikes in this window: // Turn on IPIs for this CPU/mm combination, but only // if shouldflushtlb() agrees: cpumasksetcpu(cpu, mmcpumask(next)); nexttlbgen = atomic64read(&next->context.tlbgen); choosenewasid(next, nexttlbgen, &newasid, &needflush); loadnewmmcr3(needflush); // ^ After 'needflush' is set to false, IPIs MUST // be sent to this CPU and not be ignored. thiscpuwrite(cputlbstate.loadedmm, next); // ^ Not until this point does shouldflushtlb() // become true! shouldflushtlb() will suppress TLB flushes between loadnewmmcr3() and writing to 'loadedmm', which is a window where they should not be suppressed. Whoops. === Solution === Thankfully, the fuzzy "just about to write CR3" window is already marked with loadedmm==LOADEDMMSWITCHING. Simply checking for that state in shouldflushtlb() is sufficient to ensure that the CPU is targeted with an IPI. This will cause more TLB flush IPIs. But the window is relatively small and I do not expect this to cause any kind of measurable performance impact. Update the comment where LOADEDMMSWITCHING is written since it grew yet another user. Peter Z also raised a concern that shouldflushtlb() might not observe 'loadedmm' and 'islazy' in the same order that switchmmirqsoff() writes them. Add a barrier to ensure that they are observed in the order they are written.

Affected Software

127 affected componentsFixes available

ubuntu/linux-hwe-edge*

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-azure*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gke-4.15*

ubuntu/linux-gke-5.4*

ubuntu/linux-gkeop-5.4*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-oem*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.15<5.15.0-1088.95~20.04.1

5.15.0-1088.95~20.04.1

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.15<5.15.0-1094.103~20.04.1

5.15.0-1094.103~20.04.1

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15<5.15.0-1087.96~20.04.2

5.15.0-1087.96~20.04.2

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<5.15.0-144.157~20.04.1

5.15.0-144.157~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm-5.15<5.15.0-1080.83~20.04.1

5.15.0-1080.83~20.04.1

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15<5.15.0-1083.89~20.04.1

5.15.0-1083.89~20.04.1

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-144.157~20.04.1

5.15.0-144.157~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1041.41~20.04.1

5.15.0-1041.41~20.04.1

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-5.15<5.15.0-1085.91~20.04.3

5.15.0-1085.91~20.04.3

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15<5.15.0-1083.87~20.04.1

5.15.0-1083.87~20.04.1

ubuntu/linux-riscv-5.8*

ubuntu/linux<5.15.0-144.157

5.15.0-144.157

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1088.95

5.15.0-1088.95

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-azure<5.15.0-1094.103

5.15.0-1094.103

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-fde<5.15.0-1094.103.1

5.15.0-1094.103.1

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp<5.15.0-1087.96

5.15.0-1087.96

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gke<5.15.0-1085.91

5.15.0-1085.91

ubuntu/linux-gkeop<5.15.0-1070.78

5.15.0-1070.78

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-ibm<5.15.0-1080.83

5.15.0-1080.83

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-intel-iotg<5.15.0-1083.89

5.15.0-1083.89

ubuntu/linux-kvm<5.15.0-1084.89

5.15.0-1084.89

ubuntu/linux-lowlatency<5.15.0-144.157

5.15.0-144.157

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-nvidia<5.15.0-1082.83

5.15.0-1082.83

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-tegra<5.15.0-1041.41

5.15.0-1041.41

ubuntu/linux-nvidia-tegra-igx<5.15.0-1030.30

5.15.0-1030.30

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1085.91

5.15.0-1085.91

ubuntu/linux-oracle-6.5*

ubuntu/linux-raspi<5.15.0-1083.86

5.15.0-1083.86

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp<5.15.0-1052.56

5.15.0-1052.56

ubuntu/linux-bluefield<5.15.0-1072.74

5.15.0-1072.74

ubuntu/linux-intel-iot-realtime<5.15.0-1081.83

5.15.0-1081.83

ubuntu/linux-realtime<5.15.0-1088.97

5.15.0-1088.97

ubuntu/linux-aws-fips<5.15.0-1088.95+fips1

5.15.0-1088.95+fips1

ubuntu/linux-azure-fips<5.15.0-1094.103+fips1

5.15.0-1094.103+fips1

ubuntu/linux-fips<5.15.0-144.157+fips1

5.15.0-144.157+fips1

ubuntu/linux-gcp-fips<5.15.0-1087.96+fips1

5.15.0-1087.96+fips1

ubuntu/linux-aws-6.14<6.14.0-1011.11~24.04.1

6.14.0-1011.11~24.04.1

ubuntu/linux-azure-6.11*

ubuntu/linux-gcp-6.11*

ubuntu/linux-gcp-6.14<6.14.0-1014.15~24.04.1

6.14.0-1014.15~24.04.1

ubuntu/linux-hwe-6.11*

ubuntu/linux-lowlatency-hwe-6.11*

ubuntu/linux-nvidia-6.11*

ubuntu/linux-oem-6.11*

ubuntu/linux-oem-6.14<6.14.0-1010.10

6.14.0-1010.10

ubuntu/linux-oracle-6.14<6.14.0-1011.11~24.04.1

6.14.0-1011.11~24.04.1

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv-6.14<6.14.0-28.28.1~24.04.1

6.14.0-28.28.1~24.04.1

ubuntu/linux-realtime-6.14<6.14.0-1010.10~24.04.1

6.14.0-1010.10~24.04.1

ubuntu/linux-azure-fde*

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.95~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103~20.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1087.96~20.04.2
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1080.83~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.89~20.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157~20.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1041.41~20.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1085.91~20.04.3
Upgrade
Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.87~20.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.95
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1087.96
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1085.91
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.78
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1080.83
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.89
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1084.89
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1082.83
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1041.41
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1030.30
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1085.91
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.86
Upgrade
Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.
Fixed in 5.15.0-1052.56
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1072.74
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1081.83
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.97
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.95+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1087.96+fips1
Upgrade
Upgrade ubuntu/linux-aws-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1011.11~24.04.1
Upgrade
Upgrade ubuntu/linux-gcp-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1014.15~24.04.1
Upgrade
Upgrade ubuntu/linux-oem-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1010.10
Upgrade
Upgrade ubuntu/linux-oracle-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1011.11~24.04.1
Upgrade
Upgrade ubuntu/linux-riscv-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-28.28.1~24.04.1
Upgrade
Upgrade ubuntu/linux-realtime-6.14 to a version that resolves this vulnerability.
Fixed in 6.14.0-1010.10~24.04.1
Compensating control
In the Linux x86/mm switching code, add a barrier to ensure the relevant state updates are observed in write order, and widen the window in which should_flush_tlb() sends a TLB-flush IPI so flushes are not suppressed between load_new_mm_cr3() and writing cpu_tlbstate.loaded_mm.

Event History

May 20, 2025

CVE Published

via OSV·04:15 PM

Data Sourced

via OSV·04:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

What level of access does an attacker need to exploit this issue?

The CVSS vector indicates local access and low privileges are required. User interaction is not required, but an additional attack condition must be present.

Which Ubuntu kernel packages are listed as affected?

The listed packages are linux-azure-fde, linux-realtime, linux-hwe-edge, linux-azure, linux-gcp, linux-gke, linux-gkeop, and linux-riscv.

What is the potential security impact within the affected system?

The CVSS vector rates confidentiality, integrity, and availability impact as high. The impact scope is unchanged, with no indicated impact on a separate security authority.

UBUNTU-CVE-2025-37964: High severity ubuntu/linux-hwe-edge vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

What level of access does an attacker need to exploit this issue?

Which Ubuntu kernel packages are listed as affected?

What is the potential security impact within the affected system?

Company

Resources

Contact

Frequently Asked Questions

What level of access does an attacker need to exploit this issue?

Which Ubuntu kernel packages are listed as affected?

What is the potential security impact within the affected system?