Local speculative disclosure via misindexed nospec checks
Published Aug 15, 2026 · Updated Aug 15, 2026
Improper stack-slot indexing in the Linux kernel BPF verifier allows local users to bypass Spectre v4 write sanitization. The verifier pre-check reads slot_type[i], while the write path uses (slot - i) modulo BPF_REG_SIZE, so a partial fp-8 write can inspect one half-slot and update the other without recording nospec_result. Loading the crafted program requires local BPF access; Red Hat bounds the consequence as indirect disclosure through speculative execution, while Oracle assesses a service interruption.
Summary
What happened
Improper stack-slot indexing in the Linux kernel BPF verifier allows local users to bypass Spectre v4 write sanitization. The verifier pre-check reads slot_type[i], while the write path uses (slot - i) modulo BPF_REG_SIZE, so a partial fp-8 write can inspect one half-slot and update the other without recording nospec_result. Loading the crafted program requires local BPF access; Red Hat bounds the consequence as indirect disclosure through speculative execution, while Oracle assesses a service interruption.
The record
- CVE
- CVE-2026-72428
- Published
- Aug 15, 2026
- Updated
- Aug 15, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-1285
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 15, 2026CVE publishedPublication date reported by the CVE source.
- Aug 15, 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=0b27bdf02c400684225ee5ee99970bcbf5082282
- Affected versionversion=0e9280654aa482088ee6ef3deadef331f5ac5fb0 <e62268e695075a481a6c4feeb022c19cf57422a6
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <475405593de2b796224c6297aece44f321195919
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <68b41e68a62299f26cb16af422b5c7d1c69dafd9
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <a71eb8f730a91271cf47ce291e785b6b7e54622f
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <ca119656baa8f48a56e0c2f3ab63fdd33ca9e307
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <d1d53aa30ab3b5ae89161c9cc840b3f7489ad386
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <db8f1dcf5950b91886b9df4270bc816370d292c1
- Affected versionversion=2039f26f3aca5b0e419b98f65dd36481337b86ee <f1471aa76d74e0df3b2a90731ca0208f498c670b
- Affected versionversion=4.19.207 <4.20
- Affected versionversion=5.10.56 <5.10.261
- Affected versionversion=5.13.8 <5.14
- Affected versionversion=5.14
- Affected versionversion=5.4.146 <5.5
- Affected versionversion=872968502114d68c21419cf7eb5ab97717e7b803
- Affected versionversion=f5893af2704eb763eb982f01d573f5b19f06b623
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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