cbcvebase.
CVE-2021-3761
published 2021-09-09

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…

PriorityP337high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.22%
65.5th percentile
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.

Affected

5 ranges
VendorProductVersion rangeFixed in
cloudflareoctorpki< 1.3.01.3.0
cloudflareoctorpki>= unspecified < 1.3.01.3.0
debiancfrpki< cfrpki 1.3.0-1 (bookworm)cfrpki 1.3.0-1 (bookworm)
debiandebian_linux
github.comcloudflare_cfrpki>= 0 < 1.3.01.3.0

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
osv7.5HIGH
vendor_debian7.5HIGH
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