Application crash via ELF section-count mismatch
Published Dec 31, 2021 · Updated Aug 4, 2024
Out-of-bounds write in libbpf 0.6.0 and 0.6.1 allows context-dependent attackers to crash applications via a crafted ELF object. The __bpf_object__open path trusts ELF e_shnum even when libelf derives the real section count from section zero, allocates a zero-entry section array, and writes four bytes past it. Exploitation requires an application to pass attacker-controlled ELF bytes to bpf_object__open_mem; the documented consequence is a process crash.
Summary
What happened
Out-of-bounds write in libbpf 0.6.0 and 0.6.1 allows context-dependent attackers to crash applications via a crafted ELF object. The __bpf_object__open path trusts ELF e_shnum even when libelf derives the real section count from section zero, allocates a zero-entry section array, and writes four bytes past it. Exploitation requires an application to pass attacker-controlled ELF bytes to bpf_object__open_mem; the documented consequence is a process crash.
The record
- CVE
- CVE-2021-45940
- Published
- Dec 31, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 31, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 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
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Public exploit references
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Technologies
Your stack
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Your stack
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