Description
gss_mech_free in net/sunrpc/auth_gss/gss_mech_switch.c in the rpcsec_gss_krb5 implementation in the Linux kernel through 5.6.10 lacks certain domain_release calls, leading to a memory leak. Note: This was disputed with the assertion that the issue does not grant any access not already available. It is a problem that on unloading a specific kernel module some memory is leaked, but loading kernel modules is a privileged operation. A user could also write a kernel module to consume any amount of memory they like and load that replicating the effect of this bug
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 5.7.6-1 | — |
| Debian 13 | linux | 5.7.6-1 | — |
| Debian 12 | linux | 5.7.6-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux | 5.4.0-45.49 | USN-4483-1 |
| Ubuntu 20.04 LTS | linux-aws +2 | 5.4.0-1022.22 | USN-4483-1 |
| Ubuntu 20.04 LTS | linux-azure | 5.4.0-1023.23 | USN-4483-1 |
| Ubuntu 20.04 LTS | linux-gke +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-kvm | 5.4.0-1021.21 | USN-4483-1 |
| Ubuntu 20.04 LTS | linux-oem-5.6 | 5.6.0-1031.32 | — |
| Ubuntu 20.04 LTS | linux-raspi | 5.4.0-1016.17 | USN-4483-1 |
| Ubuntu 20.04 LTS | linux-riscv | 5.4.0-31.35 | — |
| Ubuntu 18.04 LTS | linux | 4.15.0-115.116 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1080.84 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-aws-5.4 +2 | 5.4.0-1022.22~18.04.1 | USN-4483-1 |
| Ubuntu 18.04 LTS | linux-azure-4.15 | 4.15.0-1093.103 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-azure-5.4 | 5.4.0-1023.23~18.04.1 | USN-4483-1 |
| Ubuntu 18.04 LTS | linux-gcp +10 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp-4.15 | 4.15.0-1081.92 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-gke-4.15 | 4.15.0-1067.70 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-gke-5.0 | 5.0.0-1045.46 | — |
| Ubuntu 18.04 LTS | linux-gke-5.3 | 5.3.0-1032.34~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-hwe | 5.3.0-64.58~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-hwe-5.4 | 5.4.0-45.49~18.04.2 | USN-4483-1 |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1072.73 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-oem | 4.15.0-1094.104 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-oem-osp1 | 5.0.0-1065.70 | — |
| Ubuntu 18.04 LTS | linux-oracle | 4.15.0-1051.55 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-raspi-5.4 | 5.4.0-1016.17~18.04.1 | USN-4483-1 |
| Ubuntu 18.04 LTS | linux-raspi2 | 4.15.0-1068.72 | USN-4485-1 |
| Ubuntu 18.04 LTS | linux-raspi2-5.3 | 5.3.0-1030.32~18.04.2 | — |
| Ubuntu 18.04 LTS | linux-snapdragon | 4.15.0-1084.92 | USN-4485-1 |
| Ubuntu 16.04 LTS | linux | 4.4.0-186.216 | — |
| Ubuntu 16.04 LTS | linux-aws | 4.4.0-1111.123 | — |
| Ubuntu 16.04 LTS | linux-aws-hwe | 4.15.0-1080.84~16.04.1 | USN-4485-1 |
| Ubuntu 16.04 LTS | linux-azure | 4.15.0-1093.103~16.04.1 | USN-4485-1 |
| Ubuntu 16.04 LTS | linux-gcp | 4.15.0-1081.92~16.04.1 | USN-4485-1 |
| Ubuntu 16.04 LTS | linux-hwe | 4.15.0-115.116~16.04.1 | USN-4485-1 |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu 16.04 LTS | linux-kvm | 4.4.0-1077.84 | — |
| Ubuntu 16.04 LTS | linux-oracle | 4.15.0-1051.55~16.04.1 | USN-4485-1 |
| Ubuntu 16.04 LTS | linux-raspi2 | 4.4.0-1136.145 | — |
| Ubuntu 16.04 LTS | linux-snapdragon | 4.4.0-1140.148 | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro FIPS 20.04 LTS | linux-aws-fips +2 | No fix yet | — |
| Ubuntu Pro FIPS 18.04 LTS | linux-aws-fips +2 | No fix yet | — |
| Ubuntu Pro FIPS 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-aws-fips | 5.4.0-1069.73+fips2 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-azure-fips | 5.4.0-1073.76+fips1 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-gcp-fips | 5.4.0-1067.71~20.04.1 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-aws-fips | 4.15.0-2025.25 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-azure-fips | 4.15.0-2007.8 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips | 4.15.0-1039.44 | — |
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | 4.4.0-1043.48 | — |
| Ubuntu Pro 20.04 LTS | linux-azure-fde-5.15 | 5.15.0-1114.123~20.04.1 | — |
| Ubuntu Pro 14.04 LTS | linux | No fix yet | — |
| Ubuntu Pro 14.04 LTS | linux-aws | 4.4.0-1075.79 | — |
| Ubuntu Pro 14.04 LTS | linux-azure | 4.15.0-1093.103~14.04.1 | USN-4485-1 |
| Ubuntu Pro 14.04 LTS | linux-lts-xenial | 4.4.0-186.216~14.04.1 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | kernel-azure +2 | 5.3.18-18.5.1 | SUSE-SU-2020:2027-1 |
| SLES 15 SP2 | kernel-default-base | 5.3.18-24.9.1.9.2.6 | SUSE-SU-2020:2105-1 |
| SLES 15 SP2 | kernel-docs | 5.3.18-24.9.2 | SUSE-SU-2020:2105-1 |
| SLES 15 SP2 | kernel-syms +4 | 5.3.18-24.9.1 | SUSE-SU-2020:2105-1 |
| SLES 15 SP1 | kernel-azure +2 | 4.12.14-8.33.1 | SUSE-SU-2020:1604-1 |
| SLES 15 SP1 | kernel-docs +5 | 4.12.14-197.45.1 | SUSE-SU-2020:1599-1 |
| SLES 15 | kernel-docs +6 | 4.12.14-150.52.1 | SUSE-SU-2020:1663-1 |
| SLES 12 SP5 | kernel-azure +2 | 4.12.14-16.16.1 | SUSE-SU-2020:1587-1 |
| SLES 12 SP5 | kernel-docs +4 | 4.12.14-122.23.1 | SUSE-SU-2020:1602-1 |
| SLES 12 SP4 | kernel-azure +2 | 4.12.14-6.43.1 | SUSE-SU-2020:1603-1 |
| SLES 12 SP4 | kernel-docs +4 | 4.12.14-95.54.1 | SUSE-SU-2020:1605-1 |
Show 22 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | kernel-syms +2 | 4.4.180-94.121.1 | SUSE-SU-2020:1596-1 |
| SLES 12 SP3 | kgraft-patch-SLE12-SP3_Update_32 | 1-4.5.1 | SUSE-SU-2020:1596-1 |
| SLES 12 SP2 | kernel-syms +2 | 4.4.121-92.135.1 | SUSE-SU-2020:1597-1 |
| SLES 12 SP2 | kgraft-patch-SLE12-SP2_Update_35 | 1-3.5.1 | SUSE-SU-2020:1597-1 |
| SLES 11 SP4 | kernel-ec2 +8 | 3.0.101-108.117.1 | SUSE-SU-2020:14442-1 |
| SLES for SAP 15 | kernel-docs +5 | 4.12.14-150.52.1 | SUSE-SU-2020:1663-1 |
| SLES for SAP 12 SP5 | kernel-azure +2 | 4.12.14-16.16.1 | SUSE-SU-2020:1587-1 |
| SLES for SAP 12 SP5 | kernel-syms +2 | 4.12.14-122.23.1 | SUSE-SU-2020:1602-1 |
| SLES for SAP 12 SP4 | kernel-azure +2 | 4.12.14-6.43.1 | SUSE-SU-2020:1603-1 |
| SLES for SAP 12 SP4 | kernel-syms +2 | 4.12.14-95.54.1 | SUSE-SU-2020:1605-1 |
| SLES for SAP 12 SP3 | kernel-syms +2 | 4.4.180-94.121.1 | SUSE-SU-2020:1596-1 |
| SLES for SAP 12 SP3 | kgraft-patch-SLE12-SP3_Update_32 | 1-4.5.1 | SUSE-SU-2020:1596-1 |
| SLES for SAP 12 SP2 | kernel-syms +2 | 4.4.121-92.135.1 | SUSE-SU-2020:1597-1 |
| SLES for SAP 12 SP2 | kgraft-patch-SLE12-SP2_Update_35 | 1-3.5.1 | SUSE-SU-2020:1597-1 |
| SLE Real Time 12 SP5 | kernel-rt +3 | 4.12.14-10.13.1 | SUSE-SU-2020:2478-1 |
| SLE Real Time 12 SP4 | kernel-rt +3 | 4.12.14-8.23.1 | SUSE-SU-2020:2156-1 |
| SLE Live Patching 15 SP2 | kernel-default | 5.3.18-24.9.1 | SUSE-SU-2020:2105-1 |
| SLE Live Patching 15 SP2 | kernel-livepatch-SLE15-SP2_Update_1 | 1-5.3.6 | SUSE-SU-2020:2105-1 |
| SLE Live Patching 15 SP1 | kernel-default | 4.12.14-197.45.1 | SUSE-SU-2020:1599-1 |
| SLE Live Patching 15 SP1 | kernel-livepatch-SLE15-SP1_Update_12 | 1-3.5.1 | SUSE-SU-2020:1599-1 |
| SLE Live Patching 15 | kernel-default | 4.12.14-150.52.1 | SUSE-SU-2020:1663-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_18 | 1-1.5.1 | SUSE-SU-2020:1663-1 |
| SLE Live Patching 12 SP5 | kernel-default | 4.12.14-122.23.1 | SUSE-SU-2020:1602-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_5 | 1-8.3.1 | SUSE-SU-2020:1602-1 |
| SLE Live Patching 12 SP4 | kernel-default | 4.12.14-95.54.1 | SUSE-SU-2020:1605-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_14 | 1-6.3.1 | SUSE-SU-2020:1605-1 |
| SLE HPC 15 | kernel-docs +5 | 4.12.14-150.52.1 | SUSE-SU-2020:1663-1 |
| SUSE Real Time Module 15 SP1 | kernel-rt +3 | 4.12.14-14.28.1 | SUSE-SU-2020:2487-1 |
| SUSE OpenStack Cloud Crowbar 8 | kernel-syms +2 | 4.4.180-94.121.1 | SUSE-SU-2020:1596-1 |
| SUSE OpenStack Cloud Crowbar 8 | kgraft-patch-SLE12-SP3_Update_32 | 1-4.5.1 | SUSE-SU-2020:1596-1 |
| SUSE OpenStack Cloud 8 | kernel-syms +2 | 4.4.180-94.121.1 | SUSE-SU-2020:1596-1 |
| SUSE OpenStack Cloud 8 | kgraft-patch-SLE12-SP3_Update_32 | 1-4.5.1 | SUSE-SU-2020:1596-1 |
| SUSE OpenStack Cloud 7 | kernel-syms +2 | 4.4.121-92.135.1 | SUSE-SU-2020:1597-1 |
| SUSE OpenStack Cloud 7 | kgraft-patch-SLE12-SP2_Update_35 | 1-3.5.1 | SUSE-SU-2020:1597-1 |
| SUSE HPE Helion OpenStack 8 | kernel-syms +2 | 4.4.180-94.121.1 | SUSE-SU-2020:1596-1 |
| SUSE HPE Helion OpenStack 8 | kgraft-patch-SLE12-SP3_Update_32 | 1-4.5.1 | SUSE-SU-2020:1596-1 |
| SUSE Enterprise Storage 5 | kernel-syms +2 | 4.4.180-94.121.1 | SUSE-SU-2020:1596-1 |
| SUSE Enterprise Storage 5 | kgraft-patch-SLE12-SP3_Update_32 | 1-4.5.1 | SUSE-SU-2020:1596-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.2 | kernel-default-base | 5.3.18-lp152.26.2.lp152.8.2.2 | openSUSE-SU-2020:0935-1 |
| openSUSE Leap 15.2 | kernel-docs +8 | 5.3.18-lp152.26.2 | openSUSE-SU-2020:0935-1 |
| openSUSE Leap 15.2 | kernel-rt +3 | 5.3.18-lp152.3.5.1 | openSUSE-SU-2021:0242-1 |
| openSUSE Leap 15.1 | kernel-docs | 4.12.14-lp151.28.52.2 | openSUSE-SU-2020:0801-1 |
| openSUSE Leap 15.1 | kernel-obs-qa +1 | 4.12.14-lp151.28.52.3 | openSUSE-SU-2020:0801-1 |
| openSUSE Leap 15.1 | kernel-syms +5 | 4.12.14-lp151.28.52.1 | openSUSE-SU-2020:0801-1 |
Advisories 21
- USN-4485-1 linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-gcp, linux-gcp-4.15, linux-gke-4.15, linux-hwe, linux-kvm, linux-oem, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-4483-1 linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp, linux-gcp-5.4, linux-hwe-5.4, linux-kvm, linux-oracle, linux-oracle-5.4, linux-raspi, linux-raspi-5.4 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- SUSE-SU-2020:2105-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0801-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:0242-1 Security update for RT kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1596-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2156-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2487-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:14442-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0935-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1603-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2478-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1663-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1587-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1604-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1602-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1599-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:2027-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2022-1923 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 9, 2025
- SUSE-SU-2020:1597-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
- SUSE-SU-2020:1605-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
References
- https://bugzilla.kernel.org/show_bug.cgi?id=206651
- openSUSE-SU-2020:0801 vendor-advisory
- openSUSE-SU-2020:0935 vendor-advisory
- USN-4483-1 vendor-advisory
- USN-4485-1 vendor-advisory