Local privilege escalation via premature IPVS FTP unregister
Published Oct 24, 2025 · Updated Oct 24, 2025
Use-after-free in Linux IPVS FTP allows local users to gain kernel privileges by tearing down a crafted network namespace. __ip_vs_ftp_exit() unregisters ip_vs_ftp before live connections release their cp->app pointers, and ip_vs_unbind_app() later dereferences the freed objects. Local users can obtain the required namespace-scoped capability; exploitation enables kernel-memory disclosure, arbitrary kernel writes, control-flow hijacking, or a kernel panic.
Summary
What happened
Use-after-free in Linux IPVS FTP allows local users to gain kernel privileges by tearing down a crafted network namespace. __ip_vs_ftp_exit() unregisters ip_vs_ftp before live connections release their cp->app pointers, and ip_vs_unbind_app() later dereferences the freed objects. Local users can obtain the required namespace-scoped capability; exploitation enables kernel-memory disclosure, arbitrary kernel writes, control-flow hijacking, or a kernel panic.
The record
- CVE
- CVE-2025-40018
- Published
- Oct 24, 2025
- Updated
- Oct 24, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 24, 2025CVE publishedPublication date reported by the CVE source.
- Oct 24, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=2.6.39
- Affected versionversion=61b1ab4583e275af216c8454b9256de680499b19 <134121bfd99a06d44ef5ba15a9beb075297c0821
- Affected versionversion=61b1ab4583e275af216c8454b9256de680499b19 <1d79471414d7b9424d699afff2aa79fff322f52d
- Affected versionversion=61b1ab4583e275af216c8454b9256de680499b19 <53717f8a4347b78eac6488072ad8e5adbaff38d9
- Affected versionversion=61b1ab4583e275af216c8454b9256de680499b19 <8cbe2a21d85727b66d7c591fd5d83df0d8c4f757
- Affected versionversion=61b1ab4583e275af216c8454b9256de680499b19 <a343811ef138a265407167294275201621e9ebb2
- Affected versionversion=61b1ab4583e275af216c8454b9256de680499b19 <dc1a481359a72ee7e548f1f5da671282a7c13b8f
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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