High severity · published May 20, 2021
CVE-2021-28683
An issue was discovered in Envoy through 1.71.1
7.5
CVSS
1.7%
EPSS
No
On KEV
Description
An issue was discovered in Envoy through 1.71.1. There is a remotely exploitable NULL pointer dereference and crash in TLS when an unknown TLS alert code is received.
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
1.16.2; 1.17.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-28683
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-28683
Vendor Advisory
https://blog.envoyproxy.io
Third Party Advisory
https://github.com/envoyproxy/envoy/releases
Not Applicable
https://github.com/envoyproxy/envoy/security/advisories/GHSA-r22g-5f3x-xjgg
Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-xw4q-6pj2-5gfg
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