Validation stall via unbounded CA chain traversal
Published Nov 9, 2021 · Updated Sep 16, 2024
Uncontrolled recursion in NLnet Labs Routinator 0.10.1 and earlier allows remote attackers to stall RPKI validation via malicious CA chains. The validation engine follows each child CA into its chosen RRDP repository without limiting certificate-chain depth, so an endlessly extended hierarchy never completes. The attacker must control an RPKI CA and publish successive child CAs that point to different RRDP repositories; Routinator then serves stale data or, on its initial run, no data.
Summary
What happened
Uncontrolled recursion in NLnet Labs Routinator 0.10.1 and earlier allows remote attackers to stall RPKI validation via malicious CA chains. The validation engine follows each child CA into its chosen RRDP repository without limiting certificate-chain depth, so an endlessly extended hierarchy never completes. The attacker must control an RPKI CA and publish successive child CAs that point to different RRDP repositories; Routinator then serves stale data or, on its initial run, no data.
The record
- CVE
- CVE-2021-43172
- Published
- Nov 9, 2021
- Updated
- Sep 16, 2024
- Vendor
- NLnet Labs
- Product
- Routinator
- Classifications
- CWE-674, CWE-835, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 9, 2021CVE publishedPublication date reported by the CVE source.
- Sep 16, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=unspecified <=0.10.1
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Technologies
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Your stack
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