cbcvebase.
CVE-2021-32777
published 2021-08-24

CVE-2021-32777: Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions when ext-authz extension…

PriorityP350high8.3CVSS 3.1
AVNACLPRNUINSCCLILAL
EPSS
3.33%
87.1th percentile
Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions when ext-authz extension is sending request headers to the external authorization service it must merge multiple value headers according to the HTTP spec. However, only the last header value is sent. This may allow specifically crafted requests to bypass authorization. Attackers may be able to escalate privileges when using ext-authz extension or back end service that uses multiple value headers for authorization. A specifically constructed request may be delivered by an untrusted downstream peer in the presence of ext-authz extension. Envoy versions 1.19.1, 1.18.4, 1.17.4, 1.16.5 contain fixes to the ext-authz extension to correctly merge multiple request header values, when sending request for authorization.

Affected

11 ranges
VendorProductVersion rangeFixed in
envoyproxyenvoy< 1.16.51.16.5
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>= 0.11.0 < 0.14.80.14.8
github.compomerium_pomerium>= 0.15.0 < 0.15.10.15.1
pomeriumpomerium——
pomeriumpomerium——
pomeriumpomerium——
pomeriumpomerium>= 0.11.0 < 0.14.80.14.8

CVSS provenance

nvdv3.18.3HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
ghsa8.3HIGH
osv8.3HIGH
vendor_redhat8.6HIGH
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