Code execution via unchecked calloc multiplication overflow
Published Apr 30, 2021 · Updated Aug 3, 2024
Integer overflow in klibc before 2.0.9 allows attackers to corrupt heap memory through an oversized calloc allocation request. usr/klibc/calloc.c multiplies nmemb by size without checking whether the size_t product wraps, then passes the undersized result to zalloc. Exploitation requires a klibc-linked caller that accepts attacker-controlled allocation dimensions; the overwrite can crash the process or enable arbitrary code execution.
Summary
What happened
Integer overflow in klibc before 2.0.9 allows attackers to corrupt heap memory through an oversized calloc allocation request. usr/klibc/calloc.c multiplies nmemb by size without checking whether the size_t product wraps, then passes the undersized result to zalloc. Exploitation requires a klibc-linked caller that accepts attacker-controlled allocation dimensions; the overwrite can crash the process or enable arbitrary code execution.
The record
- CVE
- CVE-2021-31870
- Published
- Apr 30, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 30, 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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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