Kernel memory corruption via stale skb reuse
Published May 27, 2026 · Updated May 27, 2026
Use-after-free in Linux Kernel ovpn allows local users to corrupt kernel memory by transmitting through a local ovpn tunnel interface. During skb_list construction, skb_share_check frees a shared original skb, but ovpn_net_xmit retains and reuses its stale pointer for peer lookup, destination removal, and transmit statistics. Triggering requires local transmission and CAP_NET_ADMIN or CAP_NET_RAW, including capabilities granted in a user namespace; successful exploitation reads or corrupts kernel memory or panics the host.
Summary
What happened
Use-after-free in Linux Kernel ovpn allows local users to corrupt kernel memory by transmitting through a local ovpn tunnel interface. During skb_list construction, skb_share_check frees a shared original skb, but ovpn_net_xmit retains and reuses its stale pointer for peer lookup, destination removal, and transmit statistics. Triggering requires local transmission and CAP_NET_ADMIN or CAP_NET_RAW, including capabilities granted in a user namespace; successful exploitation reads or corrupts kernel memory or panics the host.
The record
- CVE
- CVE-2026-45929
- Published
- May 27, 2026
- Updated
- May 27, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 27, 2026CVE publishedPublication date reported by the CVE source.
- May 27, 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=08857b5ec5d91d83e69e40a36554a8c7557b7301 <3e4fbcb4e078915367ba5576cd70d76dbc970f95
- Affected versionversion=08857b5ec5d91d83e69e40a36554a8c7557b7301 <442915c96a9bff1c7080e2aedabb1c03faa28d81
- Affected versionversion=08857b5ec5d91d83e69e40a36554a8c7557b7301 <a5ec7baa44ea3a1d6aa0ca31c0ad82edf9affe41
- Affected versionversion=6.16
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