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CVE-2021-3761

OctoRPKI lacks contextual out-of-bounds check when validating RPKI ROA maxLength values

Published: Sep 9, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-787
NVD MITRE
7.5CVSSHIGH
EPSS Score
1.2%
Top 36.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-787

Affected Products

octorpkicloudflare
SaaS
Security Products / secure-gateway-vpn
debian linuxdebian
On-premOS
Operating Systems / linux-distro
github.com/cloudflare/cfrpkiGoOSS Libraries
octorpkiCloudflare
SaaS
Security Products / secure-gateway-vpn
cloudflarecommercialUSSecurity Productsaka warp, octorpki, quiche
debianoss-projectGBOperating Systemsaka debian gnu/linux
gopackage-ecosystemOSS Libraries

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9
github.com
https://www.debian.org/security/2022/dsa-5041
debian.org
https://nvd.nist.gov/vuln/detail/CVE-2021-3761
nvd.nist.gov
and 5 more references View all →

Timeline

Published
Sep 9, 2021
Last Updated
Nov 21, 2024

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