Buffer overflow in Envoyproxy Envoy

CVE-2019-18801

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.

Vulnerability class: Buffer Overflow

EPSS: 0.025 (83.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-18801?
CVE-2019-18801 is a critical-severity vulnerability in Envoyproxy Envoy, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2019-12-13.
How severe is CVE-2019-18801?
Critical severity. CVSS v3 base score is 9.8 out of 10.