CVE-2021-3761

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 v3 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:N/A:P

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	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
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

Configurations

Configuration 1 (hide)

cpe:2.3:a:cloudflare:octorpki:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

History

21 Nov 2024, 06:22

Type	Values Removed	Values Added
References	~~() https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9 - Patch, Third Party Advisory~~	() https://github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9 - Patch, Third Party Advisory
References	~~() https://www.debian.org/security/2022/dsa-5041 - Third Party Advisory~~	() https://www.debian.org/security/2022/dsa-5041 - Third Party Advisory

Information

Published : 2021-09-09 14:15

Updated : 2024-11-21 06:22

NVD link : CVE-2021-3761

Mitre link : CVE-2021-3761

CVE.ORG link : CVE-2021-3761

JSON object : View

Products Affected

cloudflare

octorpki

debian

debian_linux

CWE

CWE-787

Out-of-bounds Write

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