{"id":"CVE-2025-21766","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: use RCU protection in __ip_rt_update_pmtu()\n\n__ip_rt_update_pmtu() must use RCU protection to make\nsure the net structure it reads does not disappear.","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: use RCU protection in __ip_rt_update_pmtu()\n\n__ip_rt_update_pmtu() must use RCU protection to make\nsure the net structure it reads does not disappear.","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 4.14.200, < 4.15","linux_kernel >= 4.19.148, < 4.20","linux_kernel >= 5.4.68, < 5.5","linux_kernel >= 5.8.12, < 5.9","linux_kernel >= 5.9.1, < 5.15.179","linux_kernel >= 5.16, < 6.1.129","linux_kernel >= 6.2, < 6.6.79","linux_kernel >= 6.7, < 6.12.16","linux_kernel >= 6.13, < 6.13.4","linux_kernel = 5.9","linux_kernel = 6.14"],"patched":["linux_kernel 6.13.4"],"published":"2025-02-27","updated":"2026-07-30","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-21766","references":[{"url":"https://git.kernel.org/stable/c/139512191bd06f1b496117c76372b2ce372c9a41","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4583748b65dee4d61bd50a2214715b4237bc152a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9b1766d1ff5fe496aabe9fc5f4e34e53f35c11c4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a39f61d212d822b3062d7f70fa0588e50e55664e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ce3c6165fce0f06305c806696882a3ad4b90e33f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ea07480b23225942208f1b754fea1e7ec486d37e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd"],"epss":0.00541,"epssPercentile":0.44384,"ingestedAt":"2026-07-30T06:53:09.843Z","slug":"CVE-2025-21766","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nipv4: use RCU protection in __ip_rt_update_pmtu()\n\n__ip_rt_update_pmtu() must use RCU protection to make\nsure the net structure it reads does not disappear.\n\n## Affected\n\n- `linux_kernel >= 4.14.200, < 4.15`\n- `linux_kernel >= 4.19.148, < 4.20`\n- `linux_kernel >= 5.4.68, < 5.5`\n- `linux_kernel >= 5.8.12, < 5.9`\n- `linux_kernel >= 5.9.1, < 5.15.179`\n- `linux_kernel >= 5.16, < 6.1.129`\n- `linux_kernel >= 6.2, < 6.6.79`\n- `linux_kernel >= 6.7, < 6.12.16`\n- `linux_kernel >= 6.13, < 6.13.4`\n- `linux_kernel = 5.9`\n- `linux_kernel = 6.14`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.13.4`","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}