Description
An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel. Missing sanity may lead to a write beyond bmval[bmlen-1] in nfsd4_decode_bitmap4 in fs/nfsd/nfs4xdr.c. In this flaw, a local attacker with user privilege may gain access to out-of-bounds memory, leading to a system integrity and confidentiality threat.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | kernel | 5.11 – < 5.15.5 | 5.15.5 |
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 | 5.15.5-1 | — |
| Debian 13 | linux | 5.15.5-1 | — |
| Debian 12 | linux | 5.15.5-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | linux-aws-5.11 +1 | 5.11.0-1028.31~20.04.1 | USN-5265-1 |
| Ubuntu 20.04 LTS | linux-aws-5.13 | 5.13.0-1012.13~20.04.1 | USN-5265-1 |
| Ubuntu 20.04 LTS | linux-azure-5.11 | 5.11.0-1028.31~20.04.2 | USN-5265-1 |
| Ubuntu 20.04 LTS | linux-azure-5.13 | 5.13.0-1013.15~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-gcp-5.11 | 5.11.0-1029.33~20.04.3 | USN-5265-1 |
| Ubuntu 20.04 LTS | linux-gcp-5.13 | 5.13.0-1013.16~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-hwe-5.13 | 5.13.0-28.31~20.04.1 | USN-5265-1 |
| Ubuntu 20.04 LTS | linux-intel-5.13 | 5.13.0-1010.10 | USN-5362-1 |
| Ubuntu 20.04 LTS | linux-oem-5.13 | 5.13.0-1029.36 | USN-5265-1 |
| Ubuntu 20.04 LTS | linux-oem-5.14 | 5.14.0-1018.19 | USN-5217-1 |
| Ubuntu 20.04 LTS | linux-oracle-5.13 | 5.13.0-1016.20~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-riscv +10 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +12 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | kernel | 5.15.26.1-1 | — |
Advisories 6
- SSA-265688 SSA-265688: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1 Siemens ProductCERT · Oct 13, 2026
- USN-5362-1 linux-intel-5.13 vulnerabilities Ubuntu Security Notices (USN) · Sep 14, 2026
- USN-5265-1 linux, linux-aws, linux-aws-5.11, linux-aws-5.13, linux-azure-5.11, linux-gcp, linux-gcp-5.11, linux-hwe-5.13, linux-kvm, linux-oem-5.13, linux-oracle, linux-oracle-5.11, linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Sep 10, 2026
- ICSA-24-102-01 Siemens SIMATIC S7-1500 TM MFP CISA ICS & IT advisories · May 14, 2026
- USN-5217-1 linux-oem-5.14 vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- WID-SEC-2022-0790 Linux Kernel: Mehrere Schwachstellen ermöglichen Codeausführung BSI CERT-Bund (WID) · Mar 30, 2025
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2025101
- https://lore.kernel.org/linux-nfs/163692036074.16710.5678362976688977923.stgit%40klimt.1015granger.net/
- https://security.netapp.com/advisory/ntap-20220318-0010/
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c0019b7db1d7ac62c711cda6b357a659d46428fe