Linux vulnerability

What happened

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 versions

Linux: 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before 296f18e1c3a87c915a92ed27832d5040a22d1072 (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before 9e2182865de781c41ab16b7985e9d26dcefea867 (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before 57cc509d82b46150a11dcecc8b25eaa177eda34d (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before 368c22aea490f6f50df831b4f9e3623787686c5b (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before d1399632ba255d2e02c757af5d9f5d9279ce168c (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before d552bcfca323d175664d7444989b04f55666978a (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before 15d209bccf9273b4a8b4e579ba0e92d065b6ec8c (git); 29c5d4afba51c71cfeadd3f74f3c42e064483fb0 through before 1f3083aec8836213da441270cdb1ab612dd82cf4 (git); 2.6.23; V3.1.6 through before * (custom) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

• Apply vendor-provided updates or mitigations.
• Review affected product exposure and access logs.