CVE-2026-89606: ecryptfs: reject too-small tag 70 packets

Q: What condition triggers the vulnerable size calculation?

The issue is triggered when ecryptfs parses a malformed tag 70 packet whose body is smaller than the fixed metadata fields. Subtracting those fields to calculate the encrypted filename size can then underflow.

Q: What packet contents are required after the fix?

Tag 70 packets must contain a signature, a cipher code, and at least one byte of encrypted filename data. Packets that do not meet that minimum body size are rejected before the size subtraction.

Published Sep 11, 2026

Updated

In the Linux kernel, the following vulnerability has been resolved:

ecryptfs: reject too-small tag 70 packets

ecryptfsparsetag70packet() subtracts fixed metadata fields from the parsed packet body size to derive the encrypted filename size. A malformed packet with a body smaller than those fixed fields can underflow that size calculation.

Reject tag 70 packets before the subtraction unless the body contains the signature, cipher code, and at least one byte of encrypted filename data.

Affected Software

257 affected componentsFixes available

Linux Linux kernel

debian/linux<=6.1.176-1, <=6.12.107-1

6.1.190-16.12.115-27.2.12-17.2.15-1

debian/linux-6.12

6.12.113-1~deb12u1

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*

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<5.15.0-1119.126~20.04.1

5.15.0-1119.126~20.04.1

ubuntu/linux-aws-5.8*

ubuntu/linux-azure*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.15<5.15.0-1125.134~20.04.1

5.15.0-1125.134~20.04.1

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-azure-fde-5.15<5.15.0-1124.133~20.04.1

5.15.0-1124.133~20.04.1

ubuntu/linux-bluefield*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15<5.15.0-1120.130~20.04.1

5.15.0-1120.130~20.04.1

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<5.15.0-202.212~20.04.1

5.15.0-202.212~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm*

ubuntu/linux-ibm-5.15<5.15.0-1113.117~20.04.1

5.15.0-1113.117~20.04.1

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15<5.15.0-1114.120~20.04.1

5.15.0-1114.120~20.04.1

ubuntu/linux-iot*

ubuntu/linux-kvm*

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-197.207~20.04.1

5.15.0-197.207~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1070.72~20.04.1

5.15.0-1070.72~20.04.1

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<5.15.0-1116.122~20.04.1

5.15.0-1116.122~20.04.1

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15<5.15.0-1113.117~20.04.2

5.15.0-1113.117~20.04.2

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<5.15.0-202.212

5.15.0-202.212

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1119.126

5.15.0-1119.126

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8*

ubuntu/linux-azure<5.15.0-1125.134

5.15.0-1125.134

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8*

ubuntu/linux-azure-fde<5.15.0-1124.133

5.15.0-1124.133

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-azure-fde-6.8*

ubuntu/linux-gcp<5.15.0-1120.130

5.15.0-1120.130

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8*

ubuntu/linux-gke<5.15.0-1115.121

5.15.0-1115.121

ubuntu/linux-gkeop<5.15.0-1102.110

5.15.0-1102.110

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-ibm<5.15.0-1113.117

5.15.0-1113.117

ubuntu/linux-ibm-6.8*

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-intel-iotg<5.15.0-1114.120

5.15.0-1114.120

ubuntu/linux-kvm<5.15.0-1111.116

5.15.0-1111.116

ubuntu/linux-lowlatency<5.15.0-197.207

5.15.0-197.207

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8*

ubuntu/linux-nvidia<5.15.0-1114.115

5.15.0-1114.115

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8*

ubuntu/linux-nvidia-tegra<5.15.0-1070.72

5.15.0-1070.72

ubuntu/linux-nvidia-tegra-igx<5.15.0-1059.59

5.15.0-1059.59

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1116.122

5.15.0-1116.122

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8*

ubuntu/linux-raspi*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8*

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp*

ubuntu/linux-bluefield<5.15.0-1103.105

5.15.0-1103.105

ubuntu/linux-intel-iot-realtime<5.15.0-1111.115

5.15.0-1111.115

ubuntu/linux-realtime<5.15.0-1118.127

5.15.0-1118.127

ubuntu/linux-realtime-6.8*

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-aws-fips<5.15.0-1119.126+fips1

5.15.0-1119.126+fips1

ubuntu/linux-azure-fips<5.15.0-1125.134+fips1

5.15.0-1125.134+fips1

ubuntu/linux-fips<5.15.0-202.212+fips1

5.15.0-202.212+fips1

ubuntu/linux-gcp-fips<5.15.0-1120.130+fips1

5.15.0-1120.130+fips1

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-aws-6.14*

ubuntu/linux-aws-6.17*

ubuntu/linux-aws-7.0*

ubuntu/linux-azure*

ubuntu/linux-azure-6.11*

ubuntu/linux-azure-6.14*

ubuntu/linux-azure-6.17*

ubuntu/linux-azure-7.0*

ubuntu/linux-azure-fde*

ubuntu/linux-azure-fde-6.14*

ubuntu/linux-azure-fde-6.17*

ubuntu/linux-azure-fde-7.0*

ubuntu/linux-azure-nvidia*

ubuntu/linux-azure-nvidia-6.14*

ubuntu/linux-gcp*

ubuntu/linux-gcp-6.11*

ubuntu/linux-gcp-6.14*

ubuntu/linux-gcp-7.0*

ubuntu/linux-gke*

ubuntu/linux-gkeop*

ubuntu/linux-hwe-6.11*

ubuntu/linux-hwe-6.14*

ubuntu/linux-hwe-6.17*

ubuntu/linux-hwe-7.0<7.0.0-42.42~24.04.1

7.0.0-42.42~24.04.1

ubuntu/linux-ibm*

ubuntu/linux-lowlatency*

ubuntu/linux-lowlatency-hwe-6.11*

ubuntu/linux-nvidia*

ubuntu/linux-nvidia-6.11*

ubuntu/linux-nvidia-6.17*

ubuntu/linux-nvidia-7.0*

ubuntu/linux-nvidia-lowlatency*

ubuntu/linux-nvidia-tegra*

ubuntu/linux-oem-6.11*

ubuntu/linux-oem-6.14*

ubuntu/linux-oem-6.17*

ubuntu/linux-oem-6.8*

ubuntu/linux-oracle*

ubuntu/linux-oracle-6.14*

ubuntu/linux-oracle-6.17*

ubuntu/linux-oracle-7.0*

ubuntu/linux-raspi*

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-6.14*

ubuntu/linux-riscv-6.17*

ubuntu/linux-riscv-7.0<7.0.0-42.42.1~24.04.1

7.0.0-42.42.1~24.04.1

ubuntu/linux-xilinx*

ubuntu/linux-bluefield*

ubuntu/linux-raspi-realtime*

ubuntu/linux-realtime*

ubuntu/linux-realtime-6.14*

ubuntu/linux-realtime-6.17*

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux<7.0.0-42.42

7.0.0-42.42

ubuntu/linux-aws<7.0.0-1016.17

7.0.0-1016.17

ubuntu/linux-azure*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp<7.0.0-1016.18

7.0.0-1016.18

ubuntu/linux-gke*

ubuntu/linux-ibm<7.0.0-1017.17

7.0.0-1017.17

ubuntu/linux-nvidia*

ubuntu/linux-nvidia-bos*

ubuntu/linux-oem-7.0<7.0.0-1017.17

7.0.0-1017.17

ubuntu/linux-oracle<7.0.0-1015.16

7.0.0-1015.16

ubuntu/linux-raspi*

ubuntu/linux-realtime*

ubuntu/linux-riscv<7.0.0-42.42.1

7.0.0-42.42.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 6.1.190-1Fixed in 6.12.115-2Fixed in 7.2.12-1Fixed in 7.2.15-1
Upgrade
Upgrade debian/linux-6.12 to a version that resolves this vulnerability.
Fixed in 6.12.113-1~deb12u1
Upgrade
Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1119.126~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1125.134~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1124.133~20.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1120.130~20.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-202.212~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1113.117~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.120~20.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-197.207~20.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.72~20.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1116.122~20.04.1
Upgrade
Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1113.117~20.04.2
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-202.212
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1119.126
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1125.134
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1124.133
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1120.130
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1115.121
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1102.110
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1113.117
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.120
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1111.116
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-197.207
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.115
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.72
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1059.59
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1116.122
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1103.105
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1111.115
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1118.127
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1119.126+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1125.134+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-202.212+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1120.130+fips1
Upgrade
Upgrade ubuntu/linux-hwe-7.0 to a version that resolves this vulnerability.
Fixed in 7.0.0-42.42~24.04.1
Upgrade
Upgrade ubuntu/linux-riscv-7.0 to a version that resolves this vulnerability.
Fixed in 7.0.0-42.42.1~24.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 7.0.0-42.42
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 7.0.0-1016.17
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 7.0.0-1016.18
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 7.0.0-1017.17
Upgrade
Upgrade ubuntu/linux-oem-7.0 to a version that resolves this vulnerability.
Fixed in 7.0.0-1017.17
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 7.0.0-1015.16
Upgrade
Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.
Fixed in 7.0.0-42.42.1
Compensating control
Reject eCryptfs tag 70 packets before calculating encrypted filename size unless the packet body contains the signature, cipher code, and at least one byte of encrypted filename data.

Event History

Sep 11, 2026

CVE Published

via MITRE·07:45 PM

Data Sourced

via MITRE·07:45 PM

DescriptionSeverity

Data Sourced

via OSV·08:19 PM

DescriptionSeverityAffected Software

Data Sourced

via NVD·08:19 PM

DescriptionSeverity

Parent advisories

This vulnerability appears in the following advisories.

DSA-6528

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

What condition triggers the vulnerable size calculation?

The issue is triggered when ecryptfs parses a malformed tag 70 packet whose body is smaller than the fixed metadata fields. Subtracting those fields to calculate the encrypted filename size can then underflow.

What packet contents are required after the fix?

Tag 70 packets must contain a signature, a cipher code, and at least one byte of encrypted filename data. Packets that do not meet that minimum body size are rejected before the size subtraction.

CVE-2026-89606: ecryptfs: reject too-small tag 70 packets

Affected Software

Remediation

Event History

Parent advisories

Peer vulnerabilities

Frequently Asked Questions

What condition triggers the vulnerable size calculation?

What packet contents are required after the fix?

Company

Resources

Contact