What’s Vulnerable › Vulnerabilities

CVE-2025-21760: ndisc: extend RCU protection in ndisc_send_skb()

• Severity: high (CVSS 8.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 38.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-02-27 · updated 2026-10-15
• Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: ndisc: extend RCU protection in ndisc_send_skb() ndisc_send_skb() can be called without RTNL or RCU held. Acquire rcu_read_lock() earlier, so that we can use dev_net_rcu() and avoid a potential UAF.

Affected products

• Linux kernel: from 2.6.26 before 5.4.291; from 5.5 before 5.10.235; from 5.11 before 5.15.179; from 5.16 before 6.1.129; from 6.2 before 6.6.79; from 6.7 before 6.12.16 — fixed in 5.10.235, 5.15.179, 5.4.291, 6.1.129, 6.12.16, 6.13.4

How to fix

Upgrade to a fixed version: Linux kernel 5.10.235, 5.15.179, 5.4.291, 6.1.129. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/04e05112f10354ffc3bb6cc796d553bab161594c
• https://git.kernel.org/stable/c/10a1f3fece2f0d23a3a618b72b2b4e6f408ef7d1
• https://git.kernel.org/stable/c/4d576202b90b1b95a7c428a80b536f91b8201bcc
• https://git.kernel.org/stable/c/789230e5a8c1097301afc802e242c79bc8835c67
• https://git.kernel.org/stable/c/a9319d800b5701e7f5e3fa71a5b7c4831fc20d6d
• https://git.kernel.org/stable/c/ae38982f521621c216fc2f5182cd091f4734641d
• https://git.kernel.org/stable/c/e24d225e4cb8cf108bde00b76594499b98f0a74d
• https://git.kernel.org/stable/c/ed6ae1f325d3c43966ec1b62ac1459e2b8e45640
• https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
• https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
• https://cert-portal.siemens.com/productcert/html/ssa-019113.html
• https://cert-portal.siemens.com/productcert/html/ssa-265688.html

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