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.
CVE-2021-43173
Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2022-05-24. NVD baseline CVSS 7.5; sources differ by 0.0.
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(medium)
- EG Risk
- 39(Track)EG Risk 39/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity75% × 45%Exploitation1% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS
- 70.3%
- KEV
- Not listed
Published
November 9, 2021
Last Modified
November 21, 2024
References (6)
- sep@nlnetlabshttps://www.debian.org/security/2021/dsa-5033
- sep@nlnetlabshttps://www.debian.org/security/2022/dsa-5041
- sep@nlnetlabshttps://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txt
- af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2021/dsa-5033
- af854a3a-2127-422b-91ae-364da2661108https://www.debian.org/security/2022/dsa-5041
- af854a3a-2127-422b-91ae-364da2661108https://www.nlnetlabs.nl/downloads/routinator/CVE-2021-43172_CVE-2021-43173_CVE-2021-43174.txt
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 13× in last 7d / 50× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Showing the most recent 100 of 106 total refreshes for this CVE.
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Related CVEs(same CWE)
Same CWE
10 shownCWE-400 · CWE-755
Frequently asked(5)
What is CVE-2021-43173?
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What is the CVSS score of CVE-2021-43173?
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Dependency Blast Radius
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