Vulnerability · Published Feb 27, 2025 · Assigned by Linux
CVE-2025-21765ipv6: use RCU protection in ip6_default_advmss()
High 8.1
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 0.6% (higher than 50% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.6%top 50.5% 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: ipv6: use RCU protection in ip6_default_advmss() ip6_default_advmss() needs rcu protection to make sure the net structure it reads does not disappear.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.129-1 | DEBIAN-CVE-2025-21765 |
| Debian:13 | linux | 6.12.16-1 | DEBIAN-CVE-2025-21765 |
| Debian:14 | linux | 6.12.16-1 | DEBIAN-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux | 5.15.0-140.150 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1084.91 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | 6.8.0-1035.37~22.04.1 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1034.39 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | 6.11.0-1015.15~24.04.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | 6.8.0-1034.39~22.04.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1089.98.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | 6.8.0-1022.23 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1083.92 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | 6.11.0-1015.15~24.04.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1081.87 | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1032.36 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | 6.11.0-26.26~24.04.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1076.79 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | 6.8.0-1033.33~22.04.1 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1079.85 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1080.85 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-140.150 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | 6.11.0-1014.15~24.04.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1078.79 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | 6.11.0-1010.10 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | 6.8.0-1035.38~22.04.1 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1037.37 | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1009.9 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1026.26 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | 6.11.0-1022.22 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1081.87 | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1032.33 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-raspi | 5.15.0-1078.81 | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-raspi | 6.8.0-1035.39 | UBUNTU-CVE-2025-21765 |
| 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-2025-21765 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | 6.8.0-78.78~22.04.1 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2025-21765 |
| Ubuntu:24.04:LTS | linux-xilinx | 6.8.0-1017.18 | UBUNTU-CVE-2025-21765 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1050.54 | UBUNTU-CVE-2025-21765 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | 5578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 78ad057472d8c76e0602402269222f9f9c6987905578689a4e3c04f2d43ea39736fd3fa396d80c6e – before d02f30d220ef9511568a48dba8a9004c65f8d9045578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 28de355b63ad42309ed5a03ee7c436c90512265b5578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 84212387caadb211cd9dadd6fd5563bd37dc1f5e5578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 4176a68b0db8fc74ac14fcd00ba8231371051dc25578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 713a40c892f40300d63691d9f85b2a23b48fe1e85578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 550ed693f47370502a71b85382e7f9e6417300b85578689a4e3c04f2d43ea39736fd3fa396d80c6e – before 3c8ffcd248da34fc41e52a46e51505900115fc2a |
| Linux | Linux | 2.6.26 |
References
- https://git.kernel.org/stable/c/78ad057472d8c76e0602402269222f9f9c698790
- https://git.kernel.org/stable/c/d02f30d220ef9511568a48dba8a9004c65f8d904
- https://git.kernel.org/stable/c/28de355b63ad42309ed5a03ee7c436c90512265b
- https://git.kernel.org/stable/c/84212387caadb211cd9dadd6fd5563bd37dc1f5e
- https://git.kernel.org/stable/c/4176a68b0db8fc74ac14fcd00ba8231371051dc2
- https://git.kernel.org/stable/c/713a40c892f40300d63691d9f85b2a23b48fe1e8
- https://git.kernel.org/stable/c/550ed693f47370502a71b85382e7f9e6417300b8
- https://git.kernel.org/stable/c/3c8ffcd248da34fc41e52a46e51505900115fc2a
- 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