Description
In the Linux kernel, the following vulnerability has been resolved:
vmalloc: fix buffer overflow in vrealloc_node_align()
Commit 4c5d3365882d ("mm/vmalloc: allow to set node and align in
vrealloc") added the ability to force a new allocation if the current
pointer is on the wrong NUMA node, or if an alignment constraint is not
met, even if the user is shrinking the allocation.
On this path (need_realloc), the code allocates a new object of 'size'
bytes and then memcpy()s 'old_size' bytes into it. If the request is to
shrink the object (size < old_size), this results in an out-of-bounds
write on the new buffer.
Fix this by bounding the copy length by the new allocation size.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.18 | 6.18.27 |
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 | 7.0.4-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | linux | 7.0.0-27.27 | USN-8488-1 |
| Ubuntu 26.04 LTS | linux-aws +1 | 7.0.0-1008.8 | USN-8489-1, USN-8488-1 |
| Ubuntu 26.04 LTS | linux-azure | 7.0.0-1010.10 | USN-8603-1 |
| Ubuntu 26.04 LTS | linux-gcp +1 | 7.0.0-1007.7 | USN-8488-1 |
| Ubuntu 26.04 LTS | linux-ibm +1 | 7.0.0-1009.9 | USN-8603-1, USN-8488-1 |
| Ubuntu 26.04 LTS | linux-nvidia | 7.0.0-1013.13 | USN-8507-1 |
| Ubuntu 26.04 LTS | linux-raspi | 7.0.0-1014.14 | USN-8488-2 |
| Ubuntu 26.04 LTS | linux-riscv +1 | 7.0.0-27.27.1 | USN-8488-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-28.28~24.04.1 | USN-8569-1 |
| Ubuntu 24.04 LTS | linux-riscv +15 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 7.0.12-1.1 | openSUSE-SU-2026:11014-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.30-61.116 | 1:1.0-0.amzn2023 | ALAS2023-2026-1754 |
| Amazon Linux 2023 | perf6.18 +11 | 1:6.18.30-61.116.amzn2023 | ALAS2023-2026-1754 |
Advisories 9
- WID-SEC-2026-1827 Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 12, 2026
- USN-8603-1 linux-azure, linux-azure-fde vulnerabilities Ubuntu Security Notices (USN) · Nov 9, 2026
- USN-8488-1 linux, linux-aws, linux-gcp, linux-ibm, linux-oracle, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8569-1 linux-hwe-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8488-2 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8489-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- USN-8507-1 linux-nvidia vulnerabilities Ubuntu Security Notices (USN) · Nov 7, 2026
- ALAS2023-2026-1754 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jul 29, 2026
- openSUSE-SU-2026:11014-1 kernel-devel-7.0.12-1.1 on GA media SUSE / openSUSE Security Updates · Jun 13, 2026