CVE-2021-43173

CVE-2021-43173: Hanging RRDP request

Vendor Nlnet Labs
Product Routinator
Weakness CWE-755
Published November 9, 2021
Last update September 16, 2024

CVSS base score

What the vulnerability does

01Description

In NLnet Labs Routinator prior to 0.10.2, a validation run can be delayed significantly by an RRDP repository by not answering but slowly drip-feeding bytes to keep the connection alive. This can be used to effectively stall validation. While Routinator has a configurable time-out value for RRDP connections, this time-out was only applied to individual read or write operations rather than the complete request. Thus, if an RRDP repository sends a little bit of data before that time-out expired, it can continuously extend the time it takes for the request to finish. Since validation will only continue once the update of an RRDP repository has concluded, this delay will cause validation to stall, leading to Routinator continuing to serve the old data set or, if in the initial validation run directly after starting, never serve any data at all.

Key dates

02Disclosure timeline

November 9, 2021 CVE published
September 16, 2024 Record updated