Access-control bypass via leading-zero IPv4 misparsing
Published Mar 18, 2024 · Updated Nov 15, 2024
Improper IPv4 parsing in Net::CIDR::Lite before 0.22 allows attackers to bypass IP-based access controls with leading-zero octets. The _pack_ipv4 function accepts each octet as decimal and packs it numerically, so 010.0.0.1 becomes 10.0.0.1 while system networking interprets it as octal 8.0.0.1. Exploitation requires a dependent application to trust attacker-controlled addresses and user interaction with the affected workflow, allowing unintended IP-allowlist access.
Summary
What happened
Improper IPv4 parsing in Net::CIDR::Lite before 0.22 allows attackers to bypass IP-based access controls with leading-zero octets. The _pack_ipv4 function accepts each octet as decimal and packs it numerically, so 010.0.0.1 becomes 10.0.0.1 while system networking interprets it as octal 8.0.0.1. Exploitation requires a dependent application to trust attacker-controlled addresses and user interaction with the affected workflow, allowing unintended IP-allowlist access.
The record
- CVE
- CVE-2021-47154
- Published
- Mar 18, 2024
- Updated
- Nov 15, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- Unavailable
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 18, 2024CVE publishedPublication date reported by the CVE source.
- Nov 15, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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