Vulnerability · Published Feb 27, 2025 · Assigned by Linux
CVE-2025-21795NFSD: fix hang in nfsd4_shutdown_callback
High 7.5
In plain English
A high-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.7%top 47.9% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
In the Linux kernel, the following vulnerability has been resolved: NFSD: fix hang in nfsd4_shutdown_callback If nfs4_client is in courtesy state then there is no point to send the callback. This causes nfsd4_shutdown_callback to hang since cl_cb_inflight is not 0. This hang lasts about 15 minutes until TCP notifies NFSD that the connection was dropped. This patch modifies nfsd4_run_cb_work to skip the RPC call if nfs4_client is in courtesy state.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.129-1 | DEBIAN-CVE-2025-21795 |
| Debian:13 | linux | 6.12.16-1 | DEBIAN-CVE-2025-21795 |
| Debian:14 | linux | 6.12.16-1 | DEBIAN-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux | 5.15.0-140.150 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux | 6.8.0-78.78 | USN-7703-1 |
| Ubuntu:24.04:LTS | linux | 6.8.0-78.78 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1084.91 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1035.37 | USN-7703-1 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1035.37 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | 6.8.0-1035.37~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | 6.8.0-1035.37~22.04.1 | USN-7703-2 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1089.98 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1034.39 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | 6.11.0-1015.15~24.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | 6.8.0-1034.39~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1089.98.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | 6.8.0-1022.23 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1083.92 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1036.38 | USN-7703-2 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1036.38 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | 6.11.0-1015.15~24.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | 6.8.0-1036.38~22.04.1 | USN-7703-2 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | 6.8.0-1036.38~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1081.87 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1032.36 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1032.36 | USN-7703-4 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1066.74 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1019.21 | USN-7703-2 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1019.21 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | 6.11.0-26.26~24.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | 6.8.0-78.78~22.04.1 | USN-7703-4 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | 6.8.0-78.78~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1076.79 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1033.33 | USN-7703-2 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1033.33 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | 6.8.0-1033.33~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | 6.8.0-1033.33~22.04.1 | USN-7703-2 |
| Ubuntu:24.04:LTS | linux-intel | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1079.85 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1080.85 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-140.150 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-78.78.1 | USN-7703-1 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-78.78.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | 6.11.0-1014.15~24.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | 6.8.0-78.78.1~22.04.1 | USN-7703-1 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | 6.8.0-78.78.1~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1078.79 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-nvidia | 6.8.0-1035.38 | USN-7703-4 |
| Ubuntu:24.04:LTS | linux-nvidia | 6.8.0-1035.38 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | 6.11.0-1010.10 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | 6.8.0-1035.38~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | 6.8.0-1035.38~22.04.1 | USN-7703-4 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | 6.8.0-1035.38.1 | USN-7703-4 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | 6.8.0-1035.38.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1037.37 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1009.9 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1026.26 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | 6.11.0-1022.22 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1081.87 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1032.33 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1032.33 | USN-7703-3 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | 6.8.0-1032.33~22.04.1 | USN-7703-3 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | 6.8.0-1032.33~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-raspi | 5.15.0-1078.81 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-raspi | 6.8.0-1035.39 | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-raspi | 6.8.0-1035.39 | USN-7703-4 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | 6.8.0-78.78~22.04.1 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2025-21795 |
| Ubuntu:24.04:LTS | linux-xilinx | 6.8.0-1017.18 | UBUNTU-CVE-2025-21795 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1050.54 | UBUNTU-CVE-2025-21795 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | 67ef9e5fd737eab2495f2586df7e9ea30caa1b77 – before abed68027ea3ab893ac85cc46a00e2e64a32423926540b8940a2e21582afa61a6fb8af87310bac72 – before efa8a261c575f816c7e79a87aeb3ef8a0bd6b22166af25799940b26efd41ea6e648f75c41a48a2c2 – before 38d345f612503b850c2973e5a879f88e441b34d766af25799940b26efd41ea6e648f75c41a48a2c2 – before 23ad7797c74cd8f7f90617f1e59a8703e2b4390866af25799940b26efd41ea6e648f75c41a48a2c2 – before cedfbb92cf97a6bff3d25633001d9c44442ee85466af25799940b26efd41ea6e648f75c41a48a2c2 – before e88d2451cd42e025465d6b51fd716a47b0b3800d66af25799940b26efd41ea6e648f75c41a48a2c2 – before 036ac2778f7b28885814c6fbc07e156ad1624d035.10.220 – before 5.10.235 |
| Linux | Linux | 5.19 |
References
- https://git.kernel.org/stable/c/abed68027ea3ab893ac85cc46a00e2e64a324239
- https://git.kernel.org/stable/c/efa8a261c575f816c7e79a87aeb3ef8a0bd6b221
- https://git.kernel.org/stable/c/38d345f612503b850c2973e5a879f88e441b34d7
- https://git.kernel.org/stable/c/23ad7797c74cd8f7f90617f1e59a8703e2b43908
- https://git.kernel.org/stable/c/cedfbb92cf97a6bff3d25633001d9c44442ee854
- https://git.kernel.org/stable/c/e88d2451cd42e025465d6b51fd716a47b0b3800d
- https://git.kernel.org/stable/c/036ac2778f7b28885814c6fbc07e156ad1624d03
- https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
- https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html