Local root escalation via miscomputed eBPF bounds
Published May 27, 2021 · Updated Aug 3, 2024
Out-of-bounds memory access in the Linux kernel through 5.12.7 allows local users to gain root privileges through a crafted eBPF program. The verifier changes the pointer-arithmetic masking direction for a corner-case offset register, leaving an incorrect final aux->alu_limit and permitting accesses beyond kernel-memory bounds. Exploitation requires local code execution and permission to load an eBPF program; successful abuse permits kernel-memory reads and writes and root execution.
Summary
What happened
Out-of-bounds memory access in the Linux kernel through 5.12.7 allows local users to gain root privileges through a crafted eBPF program. The verifier changes the pointer-arithmetic masking direction for a corner-case offset register, leaving an incorrect final aux->alu_limit and permitting accesses beyond kernel-memory bounds. Exploitation requires local code execution and permission to load an eBPF program; successful abuse permits kernel-memory reads and writes and root execution.
The record
- CVE
- CVE-2021-33200
- Published
- May 27, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 27, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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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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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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