Memory disclosure and hang via malformed ext2 entries
Published Jun 22, 2026 · Updated Jun 23, 2026
Out-of-bounds read in Zephyr Project Zephyr RTOS before 4.5.0 allows physically proximate attackers to disclose memory or hang devices via ext2 media. ext2_fetch_direntry() copies de_name_len bytes without proving the entry fits the directory block, while callers advance by unchecked de_rec_len. The flaw requires ext2 support, mounted attacker-controlled storage, and a later path lookup or directory listing; readdir can expose adjacent kernel heap bytes, while a zero record length can stall traversal.
Summary
What happened
Out-of-bounds read in Zephyr Project Zephyr RTOS before 4.5.0 allows physically proximate attackers to disclose memory or hang devices via ext2 media. ext2_fetch_direntry() copies de_name_len bytes without proving the entry fits the directory block, while callers advance by unchecked de_rec_len. The flaw requires ext2 support, mounted attacker-controlled storage, and a later path lookup or directory listing; readdir can expose adjacent kernel heap bytes, while a zero record length can stall traversal.
The record
- CVE
- CVE-2026-10645
- Published
- Jun 22, 2026
- Updated
- Jun 23, 2026
- Vendor
- Zephyr Project
- Product
- Zephyr RTOS
- Classifications
- CWE-125
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 22, 2026CVE publishedPublication date reported by the CVE source.
- Jun 23, 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?
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- Affected versionversion=* <=4.4
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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