CVE-2021-43172

Infinite length chain of RRDP repositories

Description

NLnet Labs Routinator prior to 0.10.2 happily processes a chain of RRDP repositories of infinite length causing it to never finish a validation run. In RPKI, a CA can choose the RRDP repository it wishes to publish its data in. By continuously generating a new child CA that only consists of another CA using a different RRDP repository, a malicious CA can create a chain of CAs of de-facto infinite length. Routinator prior to version 0.10.2 did not contain a limit on the length of such a chain and will therefore continue to process this chain forever. As a result, the validation run will never finish, 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.

Categories

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory nlnetlabs.nl
Affected: NLnet Labs Routinator
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-43172?
CVE-2021-43172 has been scored as a high severity vulnerability.
How to fix CVE-2021-43172?
To fix CVE-2021-43172, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43172 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43172 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43172?
CVE-2021-43172 affects NLnet Labs Routinator.
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