Kernel-memory disclosure via unreset Netlink buffer headers
Published Oct 28, 2026 · Updated Oct 28, 2026
Information disclosure in Linux Netlink allows local users to infer kernel memory through crafted socket filters. In netlink_unicast() and do_one_broadcast(), network and MAC header offsets are not reset before filtering, allowing header-relative reads into uninitialized buffer headroom. The documented trigger requires unprivileged NETLINK_RDMA access and a classic socket filter on IWPM HELLO replies; reply lengths disclose headroom contents rather than arbitrary kernel memory.
Summary
What happened
Information disclosure in Linux Netlink allows local users to infer kernel memory through crafted socket filters. In netlink_unicast() and do_one_broadcast(), network and MAC header offsets are not reset before filtering, allowing header-relative reads into uninitialized buffer headroom. The documented trigger requires unprivileged NETLINK_RDMA access and a classic socket filter on IWPM HELLO replies; reply lengths disclose headroom contents rather than arbitrary kernel memory.
The record
- CVE
- CVE-2026-99211
- Published
- Oct 28, 2026
- Updated
- Oct 28, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 28, 2026CVE publishedPublication date reported by the CVE source.
- Oct 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.6.26
- Affected versionversion=b1153f29ee07dc1a788964409255a4b4fae50b98 <06791594274f87c29f1a9f1961d700272716a49d
- Affected versionversion=b1153f29ee07dc1a788964409255a4b4fae50b98 <06935da5de83aa8b98841563894857e7d2f80e47
- Affected versionversion=b1153f29ee07dc1a788964409255a4b4fae50b98 <8bf659bd54e1f00e34cf5244b1d289c506fa47c0
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Contact us