Kernel denial of service via ext4 memory leak
Published Oct 7, 2025 · Updated Oct 7, 2025
Memory exhaustion in the ext4 casefolding path in Linux allows local users to consume kernel memory through crafted filename operations. On a casefolding failure, ext4_fname_setup_filename() and ext4_fname_prepare_lookup() leave fscrypt_name.crypto_buf.name allocated instead of freeing it on the error path. Repeated failures on a writable, casefold-enabled ext4 filesystem are required; the record does not identify whether exhaustion ends in a hang or crash.
Summary
What happened
Memory exhaustion in the ext4 casefolding path in Linux allows local users to consume kernel memory through crafted filename operations. On a casefolding failure, ext4_fname_setup_filename() and ext4_fname_prepare_lookup() leave fscrypt_name.crypto_buf.name allocated instead of freeing it on the error path. Repeated failures on a writable, casefold-enabled ext4 filesystem are required; the record does not identify whether exhaustion ends in a hang or crash.
The record
- CVE
- CVE-2023-53662
- Published
- Oct 7, 2025
- Updated
- Oct 7, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-401, T1499.001
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 7, 2025CVE publishedPublication date reported by the CVE source.
- Oct 7, 2025Record 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=1ae98e295fa2577fb5e492200c58d10230e00e99 <1fb3f1bbfdb511034b0360dbeb0f6a8424ed2a5c
- Affected versionversion=1ae98e295fa2577fb5e492200c58d10230e00e99 <36daf050be3f6f067631dc52054de2d3b7cc849f
- Affected versionversion=1ae98e295fa2577fb5e492200c58d10230e00e99 <7ca4b085f430f3774c3838b3da569ceccd6a0177
- Affected versionversion=5.13
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
Public exploit references
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Technologies
Your stack
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Your stack
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