Description
A vulnerability was found in Linux Kernel where in the spk_ttyio_receive_buf2() function, it would dereference spk_ttyio_synth without checking whether it is NULL or not, and may lead to a NULL-ptr deref crash.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | kernel | kernel 5.9.14 | — |
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 | 5.9.15-1 | — |
| Debian 13 | linux | 5.9.15-1 | — |
| Debian 12 | linux | 5.9.15-1 | — |
| Debian 10 | linux | 4.19.171-2 | DSA-4843-1 |
| Debian 9 | linux-4.19 | 4.19.171-2~deb9u1 | DLA-2557-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux-realtime +1 | No fix yet | — |
| Ubuntu 20.04 LTS | linux | 5.4.0-66.74 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-aws | 5.4.0-1038.40 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-azure | 5.4.0-1040.42 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-gcp | 5.4.0-1037.40 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-gke | 5.4.0-1036.38 | — |
| Ubuntu 20.04 LTS | linux-gkeop | 5.4.0-1010.11 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-hwe-5.8 | 5.8.0-44.50~20.04.1 | USN-4751-1 |
| Ubuntu 20.04 LTS | linux-kvm | 5.4.0-1033.34 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-oem-5.6 | 5.6.0-1053.57 | USN-4912-1 |
| Ubuntu 20.04 LTS | linux-oracle | 5.4.0-1038.41 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-raspi | 5.4.0-1029.32 | USN-4750-1 |
| Ubuntu 20.04 LTS | linux-riscv +1 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-riscv-5.8 | 5.8.0-17.19~20.04.1 | — |
| Ubuntu 18.04 LTS | linux | 4.15.0-136.140 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-aws | 4.15.0-1094.101 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-aws-5.4 | 5.4.0-1038.40~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-azure-4.15 | 4.15.0-1108.120 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-azure-5.4 | 5.4.0-1040.42~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-dell300x | 4.15.0-1012.16 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-gcp +12 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp-4.15 | 4.15.0-1093.106 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-gcp-5.4 | 5.4.0-1037.40~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-gke-5.4 | 5.4.0-1036.38~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-gkeop-5.4 | 5.4.0-1010.11~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-hwe-5.4 | 5.4.0-66.74~18.04.2 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-kvm | 4.15.0-1085.87 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-oracle | 4.15.0-1065.73 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-oracle-5.4 | 5.4.0-1038.41~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-raspi-5.4 | 5.4.0-1029.32~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-raspi2 +1 | 4.15.0-1079.84 | USN-4749-1 |
| Ubuntu 18.04 LTS | linux-snapdragon | 4.15.0-1096.105 | USN-4749-1 |
| Ubuntu 16.04 LTS | linux-aws-hwe | 4.15.0-1094.101~16.04.1 | USN-4749-1 |
| Ubuntu 16.04 LTS | linux-azure | 4.15.0-1108.120~16.04.1 | USN-4749-1 |
| Ubuntu 16.04 LTS | linux-gcp | 4.15.0-1093.106~16.04.1 | USN-4749-1 |
| Ubuntu 16.04 LTS | linux-hwe | 4.15.0-136.140~16.04.1 | USN-4749-1 |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu 16.04 LTS | linux-oracle | 4.15.0-1065.73~16.04.1 | USN-4749-1 |
Show 5 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-fips +3 | 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 | 4.15.0-2037.39 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-azure-fips | 4.15.0-2020.23 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips | 4.15.0-1053.61 | — |
| Ubuntu Pro 14.04 LTS | linux-azure | 4.15.0-1108.120~14.04.1 | USN-4749-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | kernel-azure +2 | 5.3.18-18.32.1 | SUSE-SU-2021:0096-1 |
| SLES 15 SP2 | kernel-default-base | 5.3.18-24.46.1.9.19.1 | SUSE-SU-2021:0117-1 |
| SLES 15 SP2 | kernel-docs +5 | 5.3.18-24.46.1 | SUSE-SU-2021:0117-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Live Patching 15 SP2 | kernel-default | 5.3.18-24.46.1 | SUSE-SU-2021:0117-1 |
| SLE Live Patching 15 SP2 | kernel-livepatch-SLE15-SP2_Update_9 | 1-5.3.1 | SUSE-SU-2021:0117-1 |
| SUSE Real Time Module 15 SP2 | kernel-rt +3 | 5.3.18-22.1 | SUSE-SU-2021:0108-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.2 | kernel-docs +8 | 5.3.18-lp152.60.1 | openSUSE-SU-2021:0060-1 |
| openSUSE Leap 15.2 | kernel-rt +3 | 5.3.18-lp152.3.5.1 | openSUSE-SU-2021:0242-1 |
Advisories 11
- USN-4912-1 linux-oem-5.6 vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-4750-1 linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp, linux-gcp-5.4, linux-gke-5.4, linux-gkeop, linux-gkeop-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
- USN-4749-1 linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-dell300x, linux-gcp, linux-gcp-4.15, linux-gke-4.15, linux-hwe, linux-kvm, linux-oracle, linux-raspi2, linux-snapdragon vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- USN-4751-1 linux, linux-aws, linux-azure, linux-gcp, linux-hwe-5.8, linux-kvm, linux-oracle, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Jun 3, 2026
- DSA-4843-1 linux - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2557-1 linux-4.19 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2021:0108-1 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-2021:0096-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:0117-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:0060-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
References
- [oss-security] 20201208 Re: Linux kernel NULL-ptr deref bug in spk_ttyio_receive_buf2 mailing-list
- [oss-security] 20201208 Re: Linux kernel NULL-ptr deref bug in spk_ttyio_receive_buf2 mailing-list
- DSA-4843 vendor-advisory
- [debian-lts-announce] 20210212 [SECURITY] [DLA 2557-1] linux-4.19 security update mailing-list
- https://bugzilla.redhat.com/show_bug.cgi?id=1919900
- https://security.netapp.com/advisory/ntap-20210625-0004/