Local service interruption via leaked ioctl allocations
Published Apr 2, 2021 · Updated Aug 3, 2024
Memory exhaustion in the Linux kernel before 5.11.3 allows local users to interrupt service through a large Video4Linux ioctl. In video_usercopy, an ioctl larger than 128 bytes with array arguments creates two temporary allocations but stores only one pointer, leaving the first allocation unreleased. A webcam device and local access to its Video4Linux interface are required; repeated crafted calls consume kernel memory until the host becomes unavailable.
Summary
What happened
Memory exhaustion in the Linux kernel before 5.11.3 allows local users to interrupt service through a large Video4Linux ioctl. In video_usercopy, an ioctl larger than 128 bytes with array arguments creates two temporary allocations but stores only one pointer, leaving the first allocation unreleased. A webcam device and local access to its Video4Linux interface are required; repeated crafted calls consume kernel memory until the host becomes unavailable.
The record
- CVE
- CVE-2021-30002
- Published
- Apr 2, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-401, T1499
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 2, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
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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