Kernel memory leak via failed RSS query
Published Jul 19, 2026 · Updated Jul 19, 2026
Memory leak in the Linux Kernel ethtool RSS handler allows local users to consume kernel memory through failed RSS query requests. rss_prepare_get calls rss_get_data_alloc for the indirection table and hash key, but returns without freeing either buffer when get_rxfh fails. Reachability requires a network driver whose get_rxfh callback returns an error; every failing request leaves both allocations resident.
Summary
What happened
Memory leak in the Linux Kernel ethtool RSS handler allows local users to consume kernel memory through failed RSS query requests. rss_prepare_get calls rss_get_data_alloc for the indirection table and hash key, but returns without freeing either buffer when get_rxfh fails. Reachability requires a network driver whose get_rxfh callback returns an error; every failing request leaves both allocations resident.
The record
- CVE
- CVE-2026-63999
- Published
- Jul 19, 2026
- Updated
- Jul 19, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2026CVE publishedPublication date reported by the CVE source.
- Jul 19, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4f038a6a02d20859a3479293cbf172b0f14cbdd6 <266297692f97008ca48bc311775c087c59bd7fe3
- Affected versionversion=4f038a6a02d20859a3479293cbf172b0f14cbdd6 <33d05c22d6f227c5ae171c46df2f6f8bf48047ea
- Affected versionversion=4f038a6a02d20859a3479293cbf172b0f14cbdd6 <80d95d92f828cfcace955d673637d944178b435f
- Affected versionversion=5.15.181 <5.16
- Affected versionversion=5eb3fdc4b6281b29e830300c866a36d90442b1f0
- Affected versionversion=6.1.135 <6.2
- Affected versionversion=6.12.24 <6.13
- Affected versionversion=6.13.12 <6.14
- Affected versionversion=6.14.3 <6.15
- Affected versionversion=6.15
- Affected versionversion=6.6.88 <6.7
- Affected versionversion=81a5174e64ce4fb7b7a2f6499b835c904c9451ee
- Affected versionversion=a065b996052656a65afc51ad82336dc55ae4c72f
- Affected versionversion=adee9db710a6117b978a25ed4153846b7c56ec9a
- Affected versionversion=c5ed0eaddcbda56079091fc3876b140a6e70a548
- Affected versionversion=ec9faff49a4ea27731de39cb887b7e590e93157b
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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
No sourced classifications are available.
Public exploit references
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Technologies
Your stack
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Your stack
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