High severity · published May 20, 2021
CVE-2021-28682
An issue was discovered in Envoy through 1.71.1
7.5
CVSS
2%
EPSS
No
On KEV
Description
An issue was discovered in Envoy through 1.71.1. There is a remotely exploitable integer overflow in which a very large grpc-timeout value leads to unexpected timeout calculations.
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)2.0% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
1.14.6; 1.15.3; 1.16.2; 1.17.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-28682
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-28682
Vendor Advisory
https://blog.envoyproxy.io
Exploit
https://github.com/envoyproxy/envoy/blob/15e3b9dbcc9aaa9d391fa8033904aad1ea1ae70d/api/envoy/api/v2/cluster.proto#L36
Third Party Advisory
https://github.com/envoyproxy/envoy/releases
Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-r22g-5f3x-xjgg
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