CVE-2026-97592: s390/crypto: Fix missing scrub of temp buffers with AES ctr and gcm algorithm

Published Sep 25, 2026
·
Updated

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

s390/crypto: Fix missing scrub of temp buffers with AES ctr and gcm algorithm

In function ctraescrypt() there is a buffer used to process remaining bytes < AESBLOCKSIZE. This buffer was not scrubbed and thus could lead to expose of unwanted data. When the buffer is used explicitly scrub it at the end of the code block to avoid exposure of maybe sensitive data.

In a similar way the function gcmaescrypt() hat an error path where the CPACF param block was not scrubbed. Instead of return early now these error paths go to end of function where explicit scrubbing is done. Similar with the buffers which are part of the gcmsgwalk structs from the variables gwin and gwout.

Affected Software

200 affected componentsFixes available
Linux Linux kernel
Microsoft azl3 kernel 6.6.157.1-1<6.6.158.1-1
6.6.158.1-1
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-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<5.15.0-1119.126~20.04.1
5.15.0-1119.126~20.04.1
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.15<5.15.0-1125.134~20.04.1
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-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-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-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-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-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<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<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.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.6.158.1-1
  2. 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
  3. Upgrade

    Upgrade debian/linux-6.12 to a version that resolves this vulnerability.

    Fixed in 6.12.113-1~deb12u1
  4. Upgrade

    Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1119.126~20.04.1
  5. Upgrade

    Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1125.134~20.04.1
  6. 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
  7. Upgrade

    Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1120.130~20.04.1
  8. Upgrade

    Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-202.212~20.04.1
  9. Upgrade

    Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1113.117~20.04.1
  10. 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
  11. 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
  12. 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
  13. Upgrade

    Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1116.122~20.04.1
  14. Upgrade

    Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1113.117~20.04.2
  15. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 5.15.0-202.212
  16. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 5.15.0-1119.126
  17. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 5.15.0-1125.134
  18. Upgrade

    Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.

    Fixed in 5.15.0-1124.133
  19. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 5.15.0-1120.130
  20. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 5.15.0-1115.121
  21. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 5.15.0-1102.110
  22. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 5.15.0-1113.117
  23. Upgrade

    Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.

    Fixed in 5.15.0-1114.120
  24. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 5.15.0-1111.116
  25. Upgrade

    Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.

    Fixed in 5.15.0-197.207
  26. Upgrade

    Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.

    Fixed in 5.15.0-1114.115
  27. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.

    Fixed in 5.15.0-1070.72
  28. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.

    Fixed in 5.15.0-1059.59
  29. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 5.15.0-1116.122
  30. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 5.15.0-1103.105
  31. Upgrade

    Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.

    Fixed in 5.15.0-1111.115
  32. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 5.15.0-1118.127
  33. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-1119.126+fips1
  34. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-1125.134+fips1
  35. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-202.212+fips1
  36. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 5.15.0-1120.130+fips1
  37. Upgrade

    Upgrade ubuntu/linux-hwe-7.0 to a version that resolves this vulnerability.

    Fixed in 7.0.0-42.42~24.04.1
  38. 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
  39. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 7.0.0-42.42
  40. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 7.0.0-1016.17
  41. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 7.0.0-1016.18
  42. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 7.0.0-1017.17
  43. Upgrade

    Upgrade ubuntu/linux-oem-7.0 to a version that resolves this vulnerability.

    Fixed in 7.0.0-1017.17
  44. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 7.0.0-1015.16
  45. Upgrade

    Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.

    Fixed in 7.0.0-42.42.1
  46. Compensating control

    In the Linux kernel s390/crypto AES CTR and GCM implementations, explicitly scrub the temporary buffer used for remaining bytes smaller than AES_BLOCK_SIZE, the gcm_sg_walk buffers referenced by gw_in and gw_out, and the CPACF parameter block at the end of the relevant code blocks and error paths instead of returning early.

Event History

Sep 25, 2026
CVE Published
via MITRE·10:22 AM
Data Sourced
via MITRE·10:22 AM
Description
Data Sourced
via OSV·11:17 AM
DescriptionSeverityAffected Software
Data Sourced
via NVD·11:17 AM
Description
Sep 28, 2026
Data Sourced
via Microsoft·07:01 AM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

Which systems are exposed to this issue?

Systems using the Linux kernel on s390 architecture with the affected s390 crypto AES CTR or GCM code are relevant. The provided data does not identify affected kernel versions or configuration defaults.

2

What conditions are required for sensitive data to remain exposed?

The issue involves temporary buffers used during AES CTR processing of remaining data smaller than an AES block, plus AES GCM parameter and scatter-gather buffers on certain error paths. Exposure depends on those buffers not being scrubbed after use.

3

What should be done if immediate patching is not possible?

The provided fix is to explicitly scrub the temporary AES CTR buffer, the GCM CPACF parameter block, and GCM scatter-gather walk buffers, including on error paths. No alternative mitigation or workaround is provided.

Contact

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