cbcvebase.
CVE-2021-32780
published 2021-08-24

CVE-2021-32780: Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2…

PriorityP340high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.23%
65.2th percentile
Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2 connection to the CLOSED state when it receives a GOAWAY frame without any streams outstanding. The connection state is transitioned to DRAINING when it receives a SETTING frame with the SETTINGS_MAX_CONCURRENT_STREAMS parameter set to 0. Receiving these two frames in the same I/O event results in abnormal termination of the Envoy process due to invalid state transition from CLOSED to DRAINING. A sequence of H/2 frames delivered by an untrusted upstream server will result in Denial of Service in the presence of untrusted **upstream** servers. Envoy versions 1.19.1, 1.18.4 contain fixes to stop processing of pending H/2 frames after connection transition to the CLOSED state.

Affected

5 ranges
VendorProductVersion rangeFixed in
envoyproxyenvoy——
envoyproxyenvoy——
envoyproxyenvoy——
envoyproxyenvoy>= 1.18.0 < 1.18.41.18.4
github.compomerium_pomerium>= 0 < 0.15.10.15.1

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
ghsa7.5HIGH
osv7.5HIGH
vendor_redhat8.6HIGH
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