Kernel memory exhaustion via leaked PTP device name
Published May 22, 2024 · Updated May 23, 2026
Memory leak in the Linux kernel PTP subsystem allows local users to consume kernel memory by triggering a clock-registration failure. When posix_clock_register() fails, ptp_clock_register() omits put_device(), leaving the name allocated by dev_set_name() unreleased. Reachability requires a PTP clock-registration failure; public evidence does not establish an attacker-controlled trigger beyond local fault injection.
Summary
What happened
Memory leak in the Linux kernel PTP subsystem allows local users to consume kernel memory by triggering a clock-registration failure. When posix_clock_register() fails, ptp_clock_register() omits put_device(), leaving the name allocated by dev_set_name() unreleased. Reachability requires a PTP clock-registration failure; public evidence does not establish an attacker-controlled trigger beyond local fault injection.
The record
- CVE
- CVE-2021-47455
- Published
- May 22, 2024
- Updated
- May 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-401
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 22, 2024CVE publishedPublication date reported by the CVE source.
- May 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0393b8720128d5b39db8523e5bfbfc689f18c37c
- Affected versionversion=2dece4d6d13fe179ee3a5991811712725a56e2f7
- Affected versionversion=3.16.83 <3.17
- Affected versionversion=4.14.162 <4.15
- Affected versionversion=4.19.93 <4.20
- Affected versionversion=4.4.224 <4.5
- Affected versionversion=4.9.224 <4.10
- Affected versionversion=5230ef61882d2d14deb846eb6b48370694816e4c
- Affected versionversion=5.4.8 <5.5
- Affected versionversion=5.5
- Affected versionversion=6f5e3bb7879ee1eb71c6c3cbaaffbb0da6cd7d57
- Affected versionversion=89e8fc989feaac00bf1a7f9a766289422e2f5768
- Affected versionversion=a33121e5487b424339636b25c35d3a180eaa5f5e <4225fea1cb28370086e17e82c0f69bec2779dca0
- Affected versionversion=a33121e5487b424339636b25c35d3a180eaa5f5e <95c0a0c5ec8839f8f21672be786e87a100319ca8
- Affected versionversion=a33121e5487b424339636b25c35d3a180eaa5f5e <f1c96d8085588e1b997a96214b409ac3be20b524
- Affected versionversion=bfa2e0cd3dfda64fde43c3dca3aeba298d2fe7ad
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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