VDB

CVE-2025-21765

CVE-2025-21765 PUBLISHED CVSS 8.1 HIGH

ipv6: use RCU protection in ip6_default_advmss()

Reported by linux · Published February 27, 2025

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.

Fixed versions

Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.

PackageEcosystemFixed in
kernel-libbpfAmazon Linux6.1.129-138.220.amzn2023
perfAmazon Linux6.1.129-138.220.amzn2023
bpftoolAmazon Linux6.1.129-138.220.amzn2023
kernel-headersAmazon Linux6.1.129-138.220.amzn2023
kernelAmazon Linux6.1.129-138.220.amzn2023
kernel-modules-extraAmazon Linux6.1.129-138.220.amzn2023
kernel-develAmazon Linux6.1.129-138.220.amzn2023
kernel-libbpf-staticAmazon Linux6.1.129-138.220.amzn2023
kernel-livepatch-6.1.129-138.220Amazon Linux1.0-0.amzn2023
kernel-toolsAmazon Linux6.1.129-138.220.amzn2023
python3-perfAmazon Linux6.1.129-138.220.amzn2023
kernel-modules-extra-commonAmazon Linux6.1.129-138.220.amzn2023

4 more packages have a fixed version. See every fix in Lookup.

Risk scores

CVSS 3.1
8.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

VendorProductVersions
LinuxLinux5578689a4e3c04f2d43ea39736fd3fa396d80c6e, 5578689a4e3c04f2d43ea39736fd3fa396d80c6e, 5578689a4e3c04f2d43ea39736fd3fa396d80c6e
LinuxLinux2.6.26, 0, 5.4.291
amazon:2023kernel-libbpf0
linuxlinux_kernel2.6.26, 2.6.26, 2.6.26
amazon:2023perf0
SiemensSIPLUS S7-1500 CPU 1518-4 PN/DP MFP3.1.6, 3.1.7, 3.1.5
amazon:2023bpftool0
amazon:2023kernel-headers0
amazon:2023kernel0
amazon:2023kernel-modules-extra0
amazon:2023kernel-devel0
amazon:2023kernel-libbpf-static0
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystem0
amazon:2023kernel-livepatch-6.1.129-138.2200
amazon:2023kernel-tools0
amazon:2023python3-perf0
SiemensSIMATIC S7-1500 CPU 1518F-4 PN/DP MFP3.1.5, 3.1.7, 3.1.6
amazon:2023kernel-modules-extra-common0
amazon:2023kernel-tools-devel0
amazon:2023kernel-libbpf-devel0

…and 2 more

Timeline

  • Feb 26, 2025 CVE Published
  • Feb 27, 2025 EPSS Score (30 in total, the first dated here)
  • Mar 4, 2025 Coalition ESS Score (11 in total, the first dated here)
  • Dec 18, 2025 PoC Published
  • Dec 22, 2025 Security Advisory (388 in total, the first dated here)
  • Apr 29, 2026 Distribution Patch (341 in total, the first dated here)

Query this with the API

The same record, from the CLI:

vulnetix vdb vuln CVE-2025-21765
vulnetix vdb fixes CVE-2025-21765

Or with curl, using the org id and key from your account page:

curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
  "https://api.vdb.vulnetix.com/v2/vuln/CVE-2025-21765/fixes/registry"

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References

Look up in the Resolve Platform →
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