Description
An issue was discovered in net/ipv4/sysctl_net_ipv4.c in the Linux kernel before 5.0.11. There is a net/ipv4/tcp_input.c signed integer overflow in tcp_ack_update_rtt() when userspace writes a very large integer to /proc/sys/net/ipv4/tcp_min_rtt_wlen, leading to a denial of service or possibly unspecified other impact, aka CID-19fad20d15a6.
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 | 5.2.6-1 | — |
| Debian 13 | linux | 5.2.6-1 | — |
| Debian 12 | linux | 5.2.6-1 | — |
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-gke +1 | No fix yet | — |
| Ubuntu 18.04 LTS | linux | 4.15.0-60.67 | — |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1047.49 | — |
| Ubuntu 18.04 LTS | linux-azure | 5.0.0-1014.14~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-gcp | 4.15.0-1042.45 | — |
| Ubuntu 18.04 LTS | linux-gcp-edge +2 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gke-4.15 | 4.15.0-1041.43 | — |
| Ubuntu 18.04 LTS | linux-hwe | 5.0.0-23.24~18.04.1 | — |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1043.43 | — |
| Ubuntu 18.04 LTS | linux-oem | 4.15.0-1056.65 | — |
| Ubuntu 18.04 LTS | linux-oem-osp1 | 5.0.0-1015.16 | — |
| Ubuntu 18.04 LTS | linux-oracle | 4.15.0-1022.25 | — |
| Ubuntu 18.04 LTS | linux-raspi2 | 4.15.0-1044.47 | — |
| Ubuntu 18.04 LTS | linux-snapdragon | 4.15.0-1062.69 | — |
| Ubuntu 16.04 LTS | linux | 4.4.0-157.185 | — |
| Ubuntu 16.04 LTS | linux-aws | 4.4.0-1090.101 | — |
| Ubuntu 16.04 LTS | linux-aws-hwe | 4.15.0-1047.49~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-azure | 4.15.0-1056.61 | — |
| Ubuntu 16.04 LTS | linux-gcp | 4.15.0-1041.43 | — |
| Ubuntu 16.04 LTS | linux-hwe | 4.15.0-60.67~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu 16.04 LTS | linux-kvm | 4.4.0-1052.59 | — |
| Ubuntu 16.04 LTS | linux-oracle | 4.15.0-1022.25~16.04.1 | — |
| Ubuntu 16.04 LTS | linux-raspi2 | 4.4.0-1117.126 | — |
| Ubuntu 16.04 LTS | linux-snapdragon | 4.4.0-1121.127 | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro FIPS 18.04 LTS | linux-aws-fips +2 | No fix yet | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-aws-fips | 4.15.0-2018.18 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-azure-fips | 4.15.0-2006.7 | — |
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | 4.4.0-1015.20 | — |
| Ubuntu Pro 14.04 LTS | linux-aws | 4.4.0-1054.58 | — |
| Ubuntu Pro 14.04 LTS | linux-azure | 4.15.0-1059.64~14.04.1 | — |
| Ubuntu Pro 14.04 LTS | linux-lts-xenial | 4.4.0-164.192~14.04.1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | kernel-rt +12 | 4.18.0-193.rt13.51.el8 | RHSA-2020:1567 |
| RHEL 8 | perf +26 | 4.18.0-193.el8 | RHSA-2020:1769 |
| RHEL 7 | perf +13 | 4.14.0-115.18.1.el7a | RHSA-2020:0740 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | kernel-azure +2 | 4.12.14-8.22.1 | SUSE-SU-2019:3372-1 |
| SLES 15 SP1 | kernel-docs | 4.12.14-197.29.2 | SUSE-SU-2019:3317-1 |
| SLES 15 SP1 | kernel-syms +4 | 4.12.14-197.29.1 | SUSE-SU-2019:3317-1 |
| SLES 15 | kernel-azure +2 | 4.12.14-5.44.1 | SUSE-SU-2019:2951-1 |
| SLES 15 | kernel-docs +6 | 4.12.14-150.47.1 | SUSE-SU-2019:3381-1 |
| SLES 12 SP5 | kernel-azure +2 | 4.12.14-16.7.1 | SUSE-SU-2020:0093-1 |
| SLES 12 SP5 | kernel-docs +4 | 4.12.14-122.7.1 | SUSE-SU-2019:3200-1 |
| SLES 12 SP4 | kernel-azure +2 | 4.12.14-6.29.1 | SUSE-SU-2019:2953-1 |
| SLES 12 SP4 | kernel-docs +4 | 4.12.14-95.45.1 | SUSE-SU-2019:3371-1 |
| SLES 12 SP3 | kernel-syms +2 | 4.4.180-94.113.1 | SUSE-SU-2019:3379-1 |
| SLES 12 SP3 | kgraft-patch-SLE12-SP3_Update_30 | 1-4.5.1 | SUSE-SU-2019:3379-1 |
Show 16 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | kernel-syms +2 | 4.4.121-92.125.1 | SUSE-SU-2019:2984-1 |
| SLES 12 SP2 | kgraft-patch-SLE12-SP2_Update_33 | 1-3.5.1 | SUSE-SU-2019:2984-1 |
| SLES for SAP 12 SP5 | kernel-azure +2 | 4.12.14-16.7.1 | SUSE-SU-2020:0093-1 |
| SLES for SAP 12 SP5 | kernel-syms +2 | 4.12.14-122.7.1 | SUSE-SU-2019:3200-1 |
| SLES for SAP 12 SP4 | kernel-azure +2 | 4.12.14-6.29.1 | SUSE-SU-2019:2953-1 |
| SLES for SAP 12 SP4 | kernel-syms +2 | 4.12.14-95.45.1 | SUSE-SU-2019:3371-1 |
| SLES for SAP 12 SP3 | kernel-syms +2 | 4.4.180-94.113.1 | SUSE-SU-2019:3379-1 |
| SLES for SAP 12 SP3 | kgraft-patch-SLE12-SP3_Update_30 | 1-4.5.1 | SUSE-SU-2019:3379-1 |
| SLES for SAP 12 SP2 | kernel-syms +2 | 4.4.121-92.125.1 | SUSE-SU-2019:2984-1 |
| SLES for SAP 12 SP2 | kgraft-patch-SLE12-SP2_Update_33 | 1-3.5.1 | SUSE-SU-2019:2984-1 |
| SLE Real Time 12 SP4 | kernel-rt +3 | 4.12.14-8.9.3 | SUSE-SU-2019:3294-1 |
| SLE Live Patching 15 SP1 | kernel-default | 4.12.14-197.29.1 | SUSE-SU-2019:3317-1 |
| SLE Live Patching 15 SP1 | kernel-livepatch-SLE15-SP1_Update_8 | 1-3.3.1 | SUSE-SU-2019:3317-1 |
| SLE Live Patching 15 | kernel-default | 4.12.14-150.47.1 | SUSE-SU-2019:3381-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_17 | 1-1.3.2 | SUSE-SU-2019:3381-1 |
| SLE Live Patching 12 SP5 | kernel-default | 4.12.14-122.7.1 | SUSE-SU-2019:3200-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_1 | 1-8.7.1 | SUSE-SU-2019:3200-1 |
| SLE Live Patching 12 SP4 | kernel-default | 4.12.14-95.45.1 | SUSE-SU-2019:3371-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_11 | 1-6.5.1 | SUSE-SU-2019:3371-1 |
| SUSE Real Time Module 15 SP1 | kernel-rt +1 | 4.12.14-14.14.3 | SUSE-SU-2019:3295-1 |
| SUSE Real Time Module 15 SP1 | kernel-syms-rt +1 | 4.12.14-14.14.2 | SUSE-SU-2019:3295-1 |
| SUSE OpenStack Cloud Crowbar 8 | kernel-syms +2 | 4.4.180-94.113.1 | SUSE-SU-2019:3379-1 |
| SUSE OpenStack Cloud Crowbar 8 | kgraft-patch-SLE12-SP3_Update_30 | 1-4.5.1 | SUSE-SU-2019:3379-1 |
| SUSE OpenStack Cloud 8 | kernel-syms +2 | 4.4.180-94.113.1 | SUSE-SU-2019:3379-1 |
| SUSE OpenStack Cloud 8 | kgraft-patch-SLE12-SP3_Update_30 | 1-4.5.1 | SUSE-SU-2019:3379-1 |
| SUSE OpenStack Cloud 7 | kernel-syms +2 | 4.4.121-92.125.1 | SUSE-SU-2019:2984-1 |
| SUSE OpenStack Cloud 7 | kgraft-patch-SLE12-SP2_Update_33 | 1-3.5.1 | SUSE-SU-2019:2984-1 |
| SUSE HPE Helion OpenStack 8 | kernel-syms +2 | 4.4.180-94.113.1 | SUSE-SU-2019:3379-1 |
| SUSE HPE Helion OpenStack 8 | kgraft-patch-SLE12-SP3_Update_30 | 1-4.5.1 | SUSE-SU-2019:3379-1 |
| SUSE Enterprise Storage 5 | kernel-syms +2 | 4.4.180-94.113.1 | SUSE-SU-2019:3379-1 |
| SUSE Enterprise Storage 5 | kgraft-patch-SLE12-SP3_Update_30 | 1-4.5.1 | SUSE-SU-2019:3379-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | kernel-docs +8 | 4.12.14-lp151.28.32.1 | openSUSE-SU-2019:2507-1 |
| openSUSE Leap 15.0 | kernel-docs +8 | 4.12.14-lp150.12.82.1 | openSUSE-SU-2019:2503-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | perf +19 | 4.18.0-193.el8 | ELSA-2020-1769 |
Advisories 18
- RHSA-2020:1769 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Aug 22, 2026
- RHSA-2020:1567 Red Hat Security Advisory: kernel-rt security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Aug 7, 2026
- RHSA-2020:0740 Red Hat Security Advisory: kernel-alt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- SUSE-SU-2019:2951-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3372-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2503-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3295-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2953-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3294-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3381-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2984-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3371-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3379-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0093-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3317-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2507-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3200-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2020-1769 Important: kernel security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 5, 2020
References
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.0.11
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=19fad20d15a6494f47f85d869f00b11343ee5c78
- openSUSE-SU-2019:2503 vendor-advisory
- openSUSE-SU-2019:2507 vendor-advisory
- https://security.netapp.com/advisory/ntap-20191205-0001/
- RHSA-2020:0740 vendor-advisory