Root escalation via missing zerocopy reference
Published Jun 24, 2026 · Updated Jun 24, 2026
Use-after-free in Linux Kernel networking allows local users to gain root privileges through MSG_ZEROCOPY socket-buffer handling. The pskb_carve_inside_header() and pskb_carve_inside_nonlinear() helpers copy skb_shared_info.destructor_arg without acquiring a matching zerocopy reference, so repeated frees release ubuf_info_msgzc while transmitted buffers still retain the pointer. An unprivileged local user on a default kernel configuration can trigger the flaw and execute code with full root privileges.
Summary
What happened
Use-after-free in Linux Kernel networking allows local users to gain root privileges through MSG_ZEROCOPY socket-buffer handling. The pskb_carve_inside_header() and pskb_carve_inside_nonlinear() helpers copy skb_shared_info.destructor_arg without acquiring a matching zerocopy reference, so repeated frees release ubuf_info_msgzc while transmitted buffers still retain the pointer. An unprivileged local user on a default kernel configuration can trigger the flaw and execute code with full root privileges.
The record
- CVE
- CVE-2026-52943
- Published
- Jun 24, 2026
- Updated
- Jun 24, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-416, CWE-911, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 24, 2026CVE publishedPublication date reported by the CVE source.
- Jun 24, 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=4.7
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <2e0e74c59b2761a414d9f48d7bee1e45220b2427
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <474d6c771d798bca84f0a140b611e36743511e18
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <8dbed691e43a50903658130bde0fcb5abc425b37
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <96a4713ae041cc85e712bac682cd2e644004d6c6
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <98d0912e9f841e5529a5b89a972805f34cb1c69d
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <9b40bdc2a3298225dffab8158208a0d8c6300578
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <ceafb893b12f23331dcc5ff9587e643c3a40ee9f
- Affected versionversion=6fa01ccd883021105e9f8af7d04b9f156fa3494a <fd470f0a97b8e9a125f520265d2f3b088ffb5b8a
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- vn-lazyming CVE-2026-52943 local privilege-escalation PoCfunctional · demonstrated
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
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo