CVE-2026-43085

Summary

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nfnetlink_log: initialize nfgenmsg in NLMSG_DONE terminator

When batching multiple NFLOG messages (inst->qlen > 1), __nfulnl_send() appends an NLMSG_DONE terminator with sizeof(struct nfgenmsg) payload via nlmsg_put(), but never initializes the nfgenmsg bytes. The nlmsg_put() helper only zeroes alignment padding after the payload, not the payload itself, so four bytes of stale kernel heap data are leaked to userspace in the NLMSG_DONE message body.

Use nfnl_msg_put() to build the NLMSG_DONE terminator, which initializes the nfgenmsg payload via nfnl_fill_hdr(), consistent with how __build_packet_message() already constructs NFULNL_MSG_PACKET headers.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < 296f18e1c3a87c915a92ed27832d5040a22d1072affected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < 9e2182865de781c41ab16b7985e9d26dcefea867affected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < 57cc509d82b46150a11dcecc8b25eaa177eda34daffected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < 368c22aea490f6f50df831b4f9e3623787686c5baffected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < d1399632ba255d2e02c757af5d9f5d9279ce168caffected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < d552bcfca323d175664d7444989b04f55666978aaffected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < 15d209bccf9273b4a8b4e579ba0e92d065b6ec8caffected
LinuxLinux29c5d4afba51c71cfeadd3f74f3c42e064483fb0 < 1f3083aec8836213da441270cdb1ab612dd82cf4affected
LinuxLinux2.6.23affected
LinuxLinux0 < 2.6.23unaffected
LinuxLinux5.10.258 <= 5.10.*unaffected
LinuxLinux5.15.209 <= 5.15.*unaffected
LinuxLinux6.1.175 <= 6.1.*unaffected
LinuxLinux6.6.136 <= 6.6.*unaffected
LinuxLinux6.12.83 <= 6.12.*unaffected
LinuxLinux6.18.24 <= 6.18.*unaffected
LinuxLinux6.19.14 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References