CVE-2026-64137

CVE CVE-2026-64137EUVD EUVD-2026-45822Published 2026-07-19T15:40:31.000ZLast changed 2026-08-05T12:39:38.000ZCVSS 7.8

What the advisory describes

In the Linux kernel, the following vulnerability has been resolved: smb: client: require net admin for CIFS SWN netlink CIFS_GENL_CMD_SWN_NOTIFY is the userspace witness-notify command. The intended sender is the cifs.witness helper, but the generic-netlink operation currently has no capability flag, so any local process can send RESOURCE_CHANGE or CLIENT_MOVE notifications to the in-kernel witness handler. The same family exposes CIFS_GENL_MCGRP_SWN without multicast-group capability flags. Register messages sent to that group include the witness registration id and, for NTLM-authenticated mounts, the username, domain, and password attributes copied from the CIFS session. An unprivileged local process should not be able to join that group and receive those messages. Require CAP_NET_ADMIN for incoming SWN_NOTIFY commands with GENL_ADMIN_PERM, and require CAP_NET_ADMIN over the network namespace for joining the SWN multicast group with GENL_MCAST_CAP_NET_ADMIN. The cifs.witness service runs with the privileges needed for both operations.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Linux — Linux patch: 6.6.143; patch: 6.12.92; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <a8d17d22db591099519a89f14dd24810daba74c3; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <d1ebfce2c1d161186a82e77590bf7da2ea1bce91; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <969bc6370334a5b4720c5470783295d6484bbc95; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <9919021a3b7974ae66a5f9915e3a48c10cfd409b; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <a3238b09c58f323e40743ce174cd0ab81b5c09ed; patch: 6.1.176; patch: 0; 5.11; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <c2397b93fbb6f44a788fff30f99be2c20cc5e50f; fed979a7e082bd9f25f9002c3c4f8740dacd0bc8 <9cf7eb8919344932f909b2fac76296f7656fda8d; patch: 7.0.11; patch: 5.15.210; patch: 7.1; patch: 6.18.34

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

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Linux — Linux

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