CVE-2021-3909

Infinite open connection causes OctoRPKI to hang forever

Description

OctoRPKI does not limit the length of a connection, allowing for a slowloris DOS attack to take place which makes OctoRPKI wait forever. Specifically, the repository that OctoRPKI sends HTTP requests to will keep the connection open for a day before a response is returned, but does keep drip feeding new bytes to keep the connection alive.

Remediation

Solution:

  • Upgrade to 1.4

Category

4.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.73% Top 30%
Vendor Advisory debian.org Vendor Advisory debian.org
Affected: Cloudflare octorpki
Published at:
Updated at:

References

Link Tags
https://github.com/cloudflare/cfrpki/security/advisories/GHSA-8cvr-4rrf-f244 third party advisory
https://www.debian.org/security/2021/dsa-5033 third party advisory vendor advisory
https://www.debian.org/security/2022/dsa-5041 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-3909?
CVE-2021-3909 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3909?
To fix CVE-2021-3909: Upgrade to 1.4
Is CVE-2021-3909 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3909 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-2021-3909?
CVE-2021-3909 affects Cloudflare octorpki.
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