CVE-2021-41531: Invalid RPKI data could disable Route Origin Validation on RTR clients.

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-21 · updated 2026-06-17
Weakness: CWE-1288

Description

NLnet Labs Routinator prior to 0.10.0 produces invalid RTR payload if an RPKI CA uses too large values in the max-length parameter in a ROA. This will lead to RTR clients such as routers to reject the RPKI data set, effectively disabling Route Origin Validation.

Affected products

NLnet Labs Routinator: before 0.10.0 — fixed in 0.10.0

How to fix

Upgrade to a fixed version: NLnet Labs Routinator 0.10.0. Check the vendor advisory for mitigations.

References

https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-41531.txt
https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-41531.txt

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