Critical severity · published Dec 13, 2019
CVE-2019-18801
An issue was discovered in Envoy 1.12.0
9.8
CVSS
2.5%
EPSS
No
On KEV
Description
An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the heap outside of the request buffers when the upstream is HTTP/1. This may be used to corrupt nearby heap contents (leading to a query-of-death scenario) or may be used to bypass Envoy's access control mechanisms such as path based routing. An attacker can also modify requests from other users that happen to be proximal temporally and spatially.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.5% · higher than 85% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EN
Envoy · Envoyproxy
through 1.12.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-18801
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-18801
Third Party Advisory
https://access.redhat.com/errata/RHSA-2019:4222
Product
https://blog.envoyproxy.io
Patch
https://github.com/envoyproxy/envoy/commits/master
Exploit
https://github.com/envoyproxy/envoy/security/advisories/GHSA-gxvv-x4p2-rppp
groups.google.com
https://groups.google.com/forum/#%21forum/envoy-users
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