Kernel compromise via RMNET endpoint use-after-free
Published Jul 20, 2026 · Updated Jul 20, 2026
Use-after-free in the Linux Kernel RMNET driver allows local users to corrupt kernel memory via concurrent packet injection and link deletion. rmnet_dellink() removes an endpoint with hlist_del_init_rcu() but frees it immediately with kfree(), so RCU receive-path readers can dereference the stale ep->egress_dev pointer. A low-privilege user can obtain CAP_NET_ADMIN in a private user and network namespace, race crafted TUN frames against RMNET link deletion, and crash the kernel or corrupt memory for privilege escalation.
Summary
What happened
Use-after-free in the Linux Kernel RMNET driver allows local users to corrupt kernel memory via concurrent packet injection and link deletion. rmnet_dellink() removes an endpoint with hlist_del_init_rcu() but frees it immediately with kfree(), so RCU receive-path readers can dereference the stale ep->egress_dev pointer. A low-privilege user can obtain CAP_NET_ADMIN in a private user and network namespace, race crafted TUN frames against RMNET link deletion, and crash the kernel or corrupt memory for privilege escalation.
The record
- CVE
- CVE-2026-64188
- Published
- Jul 20, 2026
- Updated
- Jul 20, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 20, 2026CVE publishedPublication date reported by the CVE source.
- Jul 20, 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=4.14
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <1078ae8175777e80c9637996fb4a46c55f0ce576
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <310b93246bfec7d4452507e0c15477377ed9f025
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <41e06fcc5df0774d212e70c5b503fc769492bce3
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <8b17adf6d4fb6bf61fa4c3f58366a7c082799a71
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <9918698cf3aee4032e12bb42fd5a951dc465339b
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <c4e676c3505c5058922dc1a6f1ded795f6758135
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <d00c953a8f69921f484b629801766da68f27f658
- Affected versionversion=ceed73a2cf4aff2921802aa3d21d45280677547d <f193e38cb257d033060b63f1cfd94af076b3a2ab
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.
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
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo