Description
In the Linux kernel, the following vulnerability has been resolved:
net/handshake: duplicate handshake cancellations leak socket
When a handshake request is cancelled it is removed from the
handshake_net->hn_requests list, but it is still present in the
handshake_rhashtbl until it is destroyed.
If a second cancellation request arrives for the same handshake request,
then remove_pending() will return false... and assuming
HANDSHAKE_F_REQ_COMPLETED isn't set in req->hr_flags, we'll continue
processing through the out_true label, where we put another reference on
the sock and a refcount underflow occurs.
This can happen for example if a handshake times out - particularly if
the SUNRPC client sends the AUTH_TLS probe to the server but doesn't
follow it up with the ClientHello due to a problem with tlshd. When the
timeout is hit on the server, the server will send a FIN, which triggers
a cancellation request via xs_reset_transport(). When the timeout is
hit on the client, another cancellation request happens via
xs_tls_handshake_sync().
Add a test_and_set_bit(HANDSHAKE_F_REQ_COMPLETED) in the pending cancel
path so duplicate cancels can be detected.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.4 | 6.6.120 |
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 | 6.18.3-1 | — |
| Debian 13 | linux | 6.12.69-1 | DSA-6126-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 24.04 LTS | linux-bluefield | 6.8.0-1017.21 | — |
| Ubuntu 25.10 | linux | 6.17.0-22.22 | USN-8177-1 |
| Ubuntu 25.10 | linux-aws +1 | 6.17.0-1012.12 | USN-8183-2, USN-8183-1 |
| Ubuntu 25.10 | linux-azure +1 | 6.17.0-1013.13 | USN-8245-1 |
| Ubuntu 25.10 | linux-azure-fde | No fix yet | — |
| Ubuntu 25.10 | linux-oracle | 6.17.0-1011.11 | USN-8183-2 |
| Ubuntu 25.10 | linux-realtime | 6.17.0-1010.11 | USN-8177-1 |
| Ubuntu 25.10 | linux-riscv | 6.17.0-22.22.1 | — |
| Ubuntu 24.04 LTS | linux | 6.8.0-110.110 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-aws | 6.8.0-1052.55 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-aws-6.17 +1 | 6.17.0-1012.12~24.04.1 | USN-8183-2, USN-8183-1 |
| Ubuntu 24.04 LTS | linux-azure | 6.8.0-1054.60 | USN-8258-1 |
| Ubuntu 24.04 LTS | linux-azure-6.17 | 6.17.0-1013.13~24.04.1 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-azure-fde | 6.8.0-1058.65 | — |
| Ubuntu 24.04 LTS | linux-azure-nvidia | 6.8.0-1039.42 | — |
| Ubuntu 24.04 LTS | linux-gcp | 6.8.0-1054.57 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-gke | 6.8.0-1050.56 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-gkeop | 6.8.0-1037.40 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-hwe-6.17 | 6.17.0-22.22~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-ibm | 6.8.0-1051.51 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-lowlatency | 6.8.0-110.110.1 | USN-8179-1 |
| Ubuntu 24.04 LTS | linux-nvidia | 6.8.0-1051.54 | USN-8185-1 |
| Ubuntu 24.04 LTS | linux-nvidia-6.17 | 6.17.0-1018.18 | — |
| Ubuntu 24.04 LTS | linux-nvidia-lowlatency | 6.8.0-1051.54.1 | USN-8185-2 |
| Ubuntu 24.04 LTS | linux-nvidia-tegra | 6.8.0-1022.22 | USN-8265-1 |
| Ubuntu 24.04 LTS | linux-oem-6.17 | 6.17.0-1020.20 | USN-8245-1 |
| Ubuntu 24.04 LTS | linux-oracle | 6.8.0-1049.50 | USN-8203-1 |
| Ubuntu 24.04 LTS | linux-oracle-6.17 | 6.17.0-1011.11~24.04.1 | USN-8183-2 |
| Ubuntu 24.04 LTS | linux-raspi | 6.8.0-1052.56 | USN-8179-3 |
| Ubuntu 24.04 LTS | linux-riscv +18 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-6.17 | 6.17.0-22.22.1~24.04.1 | — |
| Ubuntu 24.04 LTS | linux-xilinx | 6.8.0-1028.29 | USN-8261-1 |
| Ubuntu 22.04 LTS | linux-aws-6.8 | 6.8.0-1052.55~22.04.1 | USN-8179-1 |
| Ubuntu 22.04 LTS | linux-azure-6.8 | 6.8.0-1059.65~22.04.1 | USN-8440-1 |
| Ubuntu 22.04 LTS | linux-azure-fde-6.8 | 6.8.0-1058.65~22.04.1 | — |
| Ubuntu 22.04 LTS | linux-gcp-6.8 | 6.8.0-1054.57~22.04.1 | USN-8179-4 |
| Ubuntu 22.04 LTS | linux-hwe-6.8 +1 | 6.8.0-110.110~22.04.1 | USN-8179-3 |
| Ubuntu 22.04 LTS | linux-ibm-6.8 | 6.8.0-1051.51~22.04.1 | USN-8179-3 |
| Ubuntu 22.04 LTS | linux-lowlatency-hwe-6.8 | 6.8.0-110.110.1~22.04.1 | USN-8179-1 |
| Ubuntu 22.04 LTS | linux-nvidia-6.8 | 6.8.0-1051.54~22.04.1 | USN-8185-1 |
| Ubuntu 22.04 LTS | linux-oracle-6.8 | 6.8.0-1049.50~22.04.1 | USN-8203-1 |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-raspi-realtime | 6.8.0-2042.43 | USN-8204-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime | 6.8.1-1047.48 | USN-8184-1 |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.17 | 6.17.0-1010.11~24.04.1 | USN-8177-2 |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime-6.8 | 6.8.1-1047.48~22.04.1 | USN-8184-1 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-aws-fips | 6.8.0-1052.55+fips1 | USN-8179-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-azure-fips | 6.8.0-1053.59+fips1 | — |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-fips | 6.8.0-110.110+fips2 | USN-8179-2 |
| Ubuntu Pro FIPS-updates 24.04 LTS | linux-gcp-fips | 6.8.0-1054.57+fips1 | USN-8179-2 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.31.1 | SUSE-SU-2026:0447-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.27.1 | SUSE-SU-2026:0472-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.31.1.150700.17.21.1 | SUSE-SU-2026:0447-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.87.1 | SUSE-SU-2026:0471-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.87.1.150600.12.40.1 | SUSE-SU-2026:0471-1 |
Show 9 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | kernel-64kb +8 | 6.12.0-160000.26.1 | SUSE-SU-2026:20599-1 |
| SLES for SAP 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20599-1 |
| SLES for SAP 15 SP6 | kernel-default-base | 6.4.0-150600.23.87.1.150600.12.40.1 | SUSE-SU-2026:0471-1 |
| SLES for SAP 15 SP6 | kernel-docs +4 | 6.4.0-150600.23.87.1 | SUSE-SU-2026:0471-1 |
| SLES 16.0 | kernel-64kb +8 | 6.12.0-160000.26.1 | SUSE-SU-2026:20615-1, SUSE-SU-2026:20599-1 |
| SLES 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20599-1 |
| SLE Micro 6.2 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | SUSE-SU-2026:20555-1 |
| SLE Micro 6.2 | kernel-rt +5 | 6.12.0-160000.26.1 | SUSE-SU-2026:20570-1, SUSE-SU-2026:20555-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20876-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20477-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20845-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20477-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.31.1 | SUSE-SU-2026:0447-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_9 | 1-150700.1.3.2 | SUSE-SU-2026:0587-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_9 | 1-150700.15.3.1 | SUSE-SU-2026:0447-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.87.1 | SUSE-SU-2026:0471-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_20 | 1-150600.13.3.1 | SUSE-SU-2026:0471-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt | 6.4.0-150700.7.31.2 | SUSE-SU-2026:0587-1 |
| SUSE Real Time Module 15 SP7 | kernel-syms-rt +1 | 6.4.0-150700.7.31.1 | SUSE-SU-2026:0587-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | kernel-default-base | 6.12.0-160000.26.1.160000.2.7 | openSUSE-SU-2026:20287-1 |
| openSUSE Leap 16.0 | kernel-rt +11 | 6.12.0-160000.26.1 | openSUSE-SU-2026:20287-1 |
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.87.1 | SUSE-SU-2026:0471-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.87.1.150600.12.40.1 | SUSE-SU-2026:0471-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.64-87.122 | 1:1.0-0.amzn2023 | ALAS2023-2026-1423 |
| Amazon Linux 2023 | perf6.12 +14 | 1:6.12.64-87.122.amzn2023 | ALAS2023-2026-1423 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | kernel | 6.6.121.1-1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | kernel-uek +34 | 6.12.0-108.64.6.3.el10uek | ELSA-2026-50112 |
| Oracle Linux 8 | bpftool +18 | 5.15.0-320.202.8.2.el9uek | ELSA-2026-50261 |
Advisories 36
- WID-SEC-2026-0086 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8440-1 linux-azure-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8179-1 linux, linux-aws, linux-aws-6.8, linux-gcp, linux-gke, linux-gkeop, linux-ibm, linux-lowlatency, linux-lowlatency-hwe-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8183-2 linux-aws, linux-aws-6.17, linux-hwe-6.17, linux-oracle, linux-oracle-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8203-1 linux-oracle, linux-oracle-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8184-1 linux-realtime, linux-realtime-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8204-1 linux-raspi-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8185-1 linux-nvidia, linux-nvidia-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8185-2 linux-nvidia-lowlatency vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8179-3 linux-hwe-6.8, linux-ibm-6.8, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8265-1 linux-nvidia-tegra vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8258-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8179-4 linux-gcp-6.8 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8183-1 linux-gcp, linux-gcp-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8245-1 linux-azure, linux-azure-6.17, linux-oem-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8177-2 linux-realtime-6.17 vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8179-2 linux-aws-fips, linux-fips, linux-gcp-fips vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8177-1 linux, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 4, 2026
- USN-8261-1 linux-xilinx vulnerabilities Ubuntu Security Notices (USN) · Sep 7, 2026
- SUSE-SU-2026:20570-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Jul 9, 2026
- ELSA-2026-50261 Important: Unbreakable Enterprise kernel security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 10, 2026
- SUSE-SU-2026:20876-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 31, 2026
- SUSE-SU-2026:20845-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 28, 2026
- openSUSE-SU-2026:20287-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20615-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20599-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20555-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20498-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20477-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0587-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0471-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0472-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0447-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- DSA-6126-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- ELSA-2026-50112 Important: Unbreakable Enterprise kernel security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Feb 20, 2026
- ALAS2023-2026-1423 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Feb 11, 2026