High severity · published Sep 9, 2021
CVE-2021-39204
Pomerium is an open source identity-aware access proxy
7.5
CVSS
1.7%
EPSS
No
On KEV
Description
Pomerium is an open source identity-aware access proxy. Envoy, which Pomerium is based on, incorrectly handles resetting of HTTP/2 streams with excessive complexity. This can lead to high CPU utilization when a large number of streams are reset. This can result in a DoS condition. Pomerium versions 0.14.8 and 0.15.1 contain an upgraded envoy binary with this vulnerability patched.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.7% · higher than 77% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
through 1.16.4; 1.17.0 before 1.17.4; 1.18.0 before 1.18.4; 1.19.0 · source: NVD
PO
Pomerium · Pomerium
before 0.14.8; 0.15.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-39204
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-39204
Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xh3-33v5-chcc
Third Party Advisory
https://github.com/pomerium/pomerium/security/advisories/GHSA-5wjf-62hw-q78r
Not Applicable
https://groups.google.com/g/envoy-announce/c/5xBpsEZZDfE/m/wD05NZBbAgAJ
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