cbcvebase.
CVE-2021-32778
published 2021-08-24

CVE-2021-32778: Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions envoy’s procedure for…

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’s procedure for resetting a HTTP/2 stream has O(N^2) complexity, leading to high CPU utilization when a large number of streams are reset. Deployments are susceptible to Denial of Service when Envoy is configured with high limit on H/2 concurrent streams. An attacker wishing to exploit this vulnerability would require a client opening and closing a large number of H/2 streams. Envoy versions 1.19.1, 1.18.4, 1.17.4, 1.16.5 contain fixes to reduce time complexity of resetting HTTP/2 streams. As a workaround users may limit the number of simultaneous HTTP/2 dreams for upstream and downstream peers to a low number, i.e. 100.

Affected

10 ranges
VendorProductVersion rangeFixed in
envoyproxyenvoy——
envoyproxyenvoy——
envoyproxyenvoy——
envoyproxyenvoy——
envoyproxyenvoy——
envoyproxyenvoy>= 1.16.0 < 1.16.51.16.5
envoyproxyenvoy>= 1.17.0 < 1.17.41.17.4
envoyproxyenvoy>= 1.18.0 < 1.18.41.18.4
github.compomerium_pomerium>= 0 < 0.14.80.14.8
github.compomerium_pomerium>= 0.15.0 < 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_redhat5.8MEDIUM
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