CVE-2026-43085
Published: May 7, 2026Last modified: June 2, 2026
Description
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.175-r0) |
| 25 LTS | linux-lts | Fixed (6.12.85-r0) | |
| Stream | linux-lts | Fixed (6.12.85-r0) |
References
- https://git.kernel.org/stable/c/15d209bccf9273b4a8b4e579ba0e92d065b6ec8c
- https://git.kernel.org/stable/c/1f3083aec8836213da441270cdb1ab612dd82cf4
- https://git.kernel.org/stable/c/296f18e1c3a87c915a92ed27832d5040a22d1072
- https://git.kernel.org/stable/c/368c22aea490f6f50df831b4f9e3623787686c5b
- https://git.kernel.org/stable/c/57cc509d82b46150a11dcecc8b25eaa177eda34d
- https://git.kernel.org/stable/c/9e2182865de781c41ab16b7985e9d26dcefea867
- https://git.kernel.org/stable/c/d1399632ba255d2e02c757af5d9f5d9279ce168c
- https://git.kernel.org/stable/c/d552bcfca323d175664d7444989b04f55666978a