Kernel memory disclosure via signed NDP offset overflow
Published Aug 22, 2026 · Updated Aug 22, 2026
Out-of-bounds read in Linux kernel USB gadget NCM code allows physically proximate attackers to read past the NDP buffer via a crafted offset. The f_ncm path stores get_ncm()'s unsigned result in signed ndp_index, letting a large offset become negative and pass unsigned bounds checks. The target must expose gadget NCM to a connected malicious USB host, and the resulting access exposes adjacent kernel memory.
Summary
What happened
Out-of-bounds read in Linux kernel USB gadget NCM code allows physically proximate attackers to read past the NDP buffer via a crafted offset. The f_ncm path stores get_ncm()'s unsigned result in signed ndp_index, letting a large offset become negative and pass unsigned bounds checks. The target must expose gadget NCM to a connected malicious USB host, and the resulting access exposes adjacent kernel memory.
The record
- CVE
- CVE-2026-74679
- Published
- Aug 22, 2026
- Updated
- Aug 22, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-125, T1200
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 22, 2026CVE publishedPublication date reported by the CVE source.
- Aug 22, 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=3.17
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <11413d7ed42174b8f5d8d0b6a25d10dc88239b21
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <5b2b3a3229a3f4c493ffdee53aee2f173b6f13b3
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <6b1c8a9403a26cb0fed7a648916c74dc236da591
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <9c8c6825a750fcd3efbe922847ca70ccd5a66857
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <a1c0deeba4a46481543d6b09c665f758c54c3a1a
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <d13f650a3485b58c124b3cda45597e8002c9c833
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <d328fdc607fa1bb668ad512e1c918a120f78f337
- Affected versionversion=370af734dfaf8336b496b386e194648e097e248a <fc9e54e22845c4da29588ca0986cb7c795b5a262
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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Public exploit references
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Technologies
Your stack
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Your stack
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