Remote code execution via kTLS record mishandling
Published Sep 5, 2025 · Updated Sep 5, 2025
Memory corruption in affected Linux kernel releases allows remote attackers to execute code via crafted records on a kTLS receive socket. When recvmsg() starts with a zero-length record from rx_list after zero-copy decryption, the receive path requeues an anchor whose backing TCP buffers have been released, causing later access to freed kernel memory. Reachability requires an established kTLS receive socket and a malicious TLS peer; exploitation exposes kernel memory, corrupts kernel state, or crashes the host.
Summary
What happened
Memory corruption in affected Linux kernel releases allows remote attackers to execute code via crafted records on a kTLS receive socket. When recvmsg() starts with a zero-length record from rx_list after zero-copy decryption, the receive path requeues an anchor whose backing TCP buffers have been released, causing later access to freed kernel memory. Reachability requires an established kTLS receive socket and a malicious TLS peer; exploitation exposes kernel memory, corrupts kernel state, or crashes the host.
The record
- CVE
- CVE-2025-39682
- Published
- Sep 5, 2025
- Updated
- Sep 5, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 5, 2025CVE publishedPublication date reported by the CVE source.
- Sep 5, 2025Record 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=6.0
- Affected versionversion=84c61fe1a75b4255df1e1e7c054c9e6d048da417 <2902c3ebcca52ca845c03182000e8d71d3a5196f
- Affected versionversion=84c61fe1a75b4255df1e1e7c054c9e6d048da417 <29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e
- Affected versionversion=84c61fe1a75b4255df1e1e7c054c9e6d048da417 <3439c15ae91a517cf3c650ea15a8987699416ad9
- Affected versionversion=84c61fe1a75b4255df1e1e7c054c9e6d048da417 <62708b9452f8eb77513115b17c4f8d1a22ebf843
- Affected versionversion=84c61fe1a75b4255df1e1e7c054c9e6d048da417 <c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677
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
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