Remote information disclosure via KSM timing side channel
Published Aug 23, 2022 · Updated Aug 3, 2024
Information disclosure in Linux Kernel KSM allows remote attackers to infer memory contents through page-sized uploads and response timing. KSM merges identical anonymous pages into shared copy-on-write mappings, and a resulting access-time change reveals whether attacker-chosen content matches a merged page. Exploitation requires enabled KSM and a network service that accepts controlled page-sized content; demonstrated consequences include database-record inference and KASLR disclosure.
Summary
What happened
Information disclosure in Linux Kernel KSM allows remote attackers to infer memory contents through page-sized uploads and response timing. KSM merges identical anonymous pages into shared copy-on-write mappings, and a resulting access-time change reveals whether attacker-chosen content matches a merged page. Exploitation requires enabled KSM and a network service that accepts controlled page-sized content; demonstrated consequences include database-record inference and KASLR disclosure.
The record
- CVE
- CVE-2021-3714
- Published
- Aug 23, 2022
- Updated
- Aug 3, 2024
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- Unavailable
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 23, 2022CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
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- Affected versionversion=Not known
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
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Public exploit references
- Remote Memory-Deduplication Attacks proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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