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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
7.5HIGH
NVD MITRE
EPSS Score
1.2%
Top 34.3%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

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

Cloudflare
commercial·USaka quiche, warp, octorpki
octorpkiOn-premSecurity Product
Security Products / pki-crypto
debian
oss-project·GBaka debian gnu/linux
debian linuxOn-premOS
Operating Systems / linux-distro
Go
package-ecosystem
github.com/cloudflare/cfrpki
OSS Libraries
and 1 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

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 →

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