Description
An information disclosure vulnerability exists in the /proc/pid/syscall functionality of Linux Kernel 5.1 Stable and 5.4.66. More specifically, this issue has been introduced in v5.1-rc4 (commit 631b7abacd02b88f4b0795c08b54ad4fc3e7c7c0) and is still present in v5.10-rc4, so it’s likely that all versions in between are affected. An attacker can read /proc/pid/syscall to trigger this vulnerability, which leads to the kernel leaking memory contents.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | Linux Kernel | Linux Kernel v5.10-rc4,Linux Kernel v5.4.66,Linux Kernel v5.9.8 | — |
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 | — |
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 | 5.6.0-1048.52 | USN-4752-1 |
| 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-aws-5.4 | 5.4.0-1038.40~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-azure-5.4 | 5.4.0-1040.42~18.04.1 | USN-4750-1 |
| Ubuntu 18.04 LTS | linux-gcp +12 | No fix yet | — |
| 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-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 16.04 LTS | linux-hwe-edge | No fix yet | — |
Show 2 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-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 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | kernel-uek +4 | 5.4.17-2102.200.13.el8uek | ELSA-2021-9140 |
| Oracle Linux 7 | kernel-uek-container +1 | 5.4.17-2102.200.13.el8 | ELSA-2021-9141 |
| Oracle Linux 7 | perf +3 | 5.4.17-2102.200.13.el7uek | ELSA-2021-9140 |
Advisories 5
- USN-4752-1 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-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
- ELSA-2021-9141 Important: Unbreakable Enterprise kernel-container security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Mar 31, 2021
- ELSA-2021-9140 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Mar 31, 2021