High 8.1Published Feb 26, 2025

CVE-2025-21766ipv4: use RCU protection in __ip_rt_update_pmtu()

Updated under an hour ago (Oct 27, 2026, 8:40 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: ipv4: use RCU protection in __ip_rt_update_pmtu() __ip_rt_update_pmtu() must use RCU protection to make sure the net structure it reads does not disappear.

CVSS: 8.1 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 15, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 before ce3c6165fce0f06305c806696882a3ad4b90e33f; from 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 before ea07480b23225942208f1b754fea1e7ec486d37e; from 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 before 9b1766d1ff5fe496aabe9fc5f4e34e53f35c11c4; from 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 before 4583748b65dee4d61bd50a2214715b4237bc152a; from 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 before a39f61d212d822b3062d7f70fa0588e50e55664e; from 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 before 139512191bd06f1b496117c76372b2ce372c9a41; f415c264176e6095e9dee823e09c5bdd0ee0d337; 98776a365da509ad923083ae54b38ee521c52742; and 6 more ranges	CNA record
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name)	from V3.1.5	CISA ADP
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name)	all versions	CISA ADP
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name)	from V3.1.5	CISA ADP
linux linux_kernel linux:linux_kernel	from 4.14.200 before 4.15; from 4.19.148 before 4.20; from 5.4.68 before 5.5; from 5.8.12 before 5.9; from 5.9.1 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; and 6 more ranges	NVD

References

References

https://git.kernel.org/stable/c/ce3c6165fce0f06305c806696882a3ad4b90e33f	patch
https://git.kernel.org/stable/c/ea07480b23225942208f1b754fea1e7ec486d37e	patch
https://git.kernel.org/stable/c/9b1766d1ff5fe496aabe9fc5f4e34e53f35c11c4	patch
https://git.kernel.org/stable/c/4583748b65dee4d61bd50a2214715b4237bc152a	patch
https://git.kernel.org/stable/c/a39f61d212d822b3062d7f70fa0588e50e55664e	patch
https://git.kernel.org/stable/c/139512191bd06f1b496117c76372b2ce372c9a41	patch
https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
https://cert-portal.siemens.com/productcert/html/ssa-784472.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.