CVE-2021-3761
Cloudflare OctoRPKI RPKI Origin Validation Truncation
Description
Any CA issuer in the RPKI can trick OctoRPKI prior to 1.3.0 into emitting an invalid VRP "MaxLength" value, causing RTR sessions to terminate. An attacker can use this to disable RPKI Origin Validation in a victim network (for example AS 13335 - Cloudflare) prior to launching a BGP hijack which during normal operations would be rejected as "RPKI invalid". Additionally, in certain deployments RTR session flapping in and of itself also could cause BGP routing churn, causing availability issues.
INFO
Published Date :
Sept. 9, 2021, 2:15 p.m.
Last Modified :
April 4, 2022, 1:41 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.6
Exploitability Score :
3.9
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-3761.
| URL | Resource |
|---|---|
| https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9 | Patch Third Party Advisory |
| https://www.debian.org/security/2022/dsa-5041 | Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-3761 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-3761 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Modified Analysis by [email protected]
Apr. 04, 2022
Action Type Old Value New Value Changed Reference Type https://www.debian.org/security/2022/dsa-5041 No Types Assigned https://www.debian.org/security/2022/dsa-5041 Third Party Advisory Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* -
CVE Modified by [email protected]
Jan. 12, 2022
Action Type Old Value New Value Added Reference https://www.debian.org/security/2022/dsa-5041 [No Types Assigned] -
Initial Analysis by [email protected]
Sep. 24, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:N/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9 No Types Assigned https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9 Patch, Third Party Advisory Added CWE NIST CWE-787 Added CPE Configuration OR *cpe:2.3:a:cloudflare:octorpki:*:*:*:*:*:*:*:* versions up to (excluding) 1.3.0 -
CVE Modified by [email protected]
Sep. 09, 2021
Action Type Old Value New Value Changed Description Any CA issuer in the RPKI can trick OctoRPKI prior to 1.3.0 into emitting an invalid VRP "MaxLength" value, causing RTR sessions to terminate. An attacker can use this to disable RPKI Origin Validation in a victim network (for example AS 13335 - Cloudflare) prior to launching a BGP hijack which during normal operations would be rejected as "RPKI invalid". Additionally, in certain deployments RTR session flapping in and of itself also could cause BGP routing churn, causing availability issues. Any CA issuer in the RPKI can trick OctoRPKI prior to 1.3.0 into emitting an invalid VRP "MaxLength" value, causing RTR sessions to terminate. An attacker can use this to disable RPKI Origin Validation in a victim network (for example AS 13335 - Cloudflare) prior to launching a BGP hijack which during normal operations would be rejected as "RPKI invalid". Additionally, in certain deployments RTR session flapping in and of itself also could cause BGP routing churn, causing availability issues.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-3761 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-3761
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.11 }} 0.03%
score
0.45357
percentile