Vulnerability in Envoyproxy Envoy

CVE-2019-9901

Envoy 1.9.0 and before does not normalize HTTP URL paths. A remote attacker may craft a relative path, e.g., something/../admin, to bypass access control, e.g., a block on /admin. A backend server could then interpret the non-normalized path and provide an attacker access beyond the scope provided for by the access control policy.

EPSS: 0.027 (84.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2019-9901?
CVE-2019-9901 is a medium-severity vulnerability in Envoyproxy Envoy, classified under Use of Incorrectly-Resolved Name or Reference. CVSS score: 6.5/10. Published 2019-04-25.
How severe is CVE-2019-9901?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2019-9901 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.