Kernel heap disclosure via unchecked packet length
Published Jul 27, 2026 · Updated Jul 27, 2026
Out-of-bounds read in the Linux Kernel GL620A USB driver allows remote attackers to disclose kernel heap data over an attached cable. genelink_rx_fixup() trusts a device-supplied packet length bounded only by 1514 bytes and copies that amount before verifying the received buffer contains it. A malicious peer on an active GeneLink host-to-host cable can receive adjacent slab contents, and an over-read into unmapped memory can also panic the host.
Summary
What happened
Out-of-bounds read in the Linux Kernel GL620A USB driver allows remote attackers to disclose kernel heap data over an attached cable. genelink_rx_fixup() trusts a device-supplied packet length bounded only by 1514 bytes and copies that amount before verifying the received buffer contains it. A malicious peer on an active GeneLink host-to-host cable can receive adjacent slab contents, and an over-read into unmapped memory can also panic the host.
The record
- CVE
- CVE-2026-64540
- Published
- Jul 27, 2026
- Updated
- Jul 27, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1200
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 27, 2026CVE publishedPublication date reported by the CVE source.
- Jul 27, 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=2.6.14
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <0575599e451aff3c5329922562374a2cab25fc51
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <0a7d9c7c5f1f208c523abbb4db6aea7bc1fad3db
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <255d03551f94c7bdd86c7d9181a70b21917d829f
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <3ef79fa3860e644c8de7834fa7300e1c58f38862
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <4359376e6238d89977a35086e47ca3b07f43e850
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <573418f7ea8f859a841417eb4b915594094fd967
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <8624e179fa3ce23c2fbd1a198ce30764b73f054a
- Affected versionversion=47ee3051c856cc2aa95d35d577a8cb37279d540f <8ff7f2a6da4fccaa5cc9be7251a24e71e29fbd1a
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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