PT-2020-6649 · Nginx+6 · Nginx+6

Bert Jw Regeer + 1 · Published 2020-01-09 · Updated 2026-04-21 · CVE-2019-20372

Positive Technologies (AI Summary)

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Name of the Vulnerable Software and Affected Versions NGINX versions prior to 1.17.7

Description The issue is related to HTTP request smuggling in NGINX, which can be exploited by an attacker to read unauthorized web pages, particularly in environments where NGINX is fronted by a load balancer. This is due to insufficient handling of HTTP requests. The vulnerability can allow a remote attacker to gain unauthorized access to information.

Recommendations For NGINX versions prior to 1.17.7, update to version 1.17.7 or later to resolve the issue. For versions prior to 1.21.0, updating to version 1.21.0 can also address multiple related issues, including this one.

Exploit

Fix

HTTP Request/Response Smuggling

Weakness Enumeration

CWE-444

Related Identifiers

ALT-PU-2020-2636

ALT-PU-2020-2686

BDU:2022-02389

CESA-2020_5495

CLEANSTART-2026-AF45008

CLEANSTART-2026-BA37192

CLEANSTART-2026-MQ02912

CLEANSTART-2026-XB16901

CLEANSTART-2026-ZN32454

CLEANSTART-2026-ZT77083

CVE-2019-20372

ELSA-2020-5495

MGASA-2020-0231

OPENSUSE-SU-2020:0204-1

OPENSUSE-SU-2020_0204-1

OPENSUSE-SU-2024:11092-1

RHSA-2020:2817

RHSA-2020:5495

RHSA-2020_5495

SUSE-SU-2020:0348-1

SUSE-SU-2020:1171-1

SUSE-SU-2020_0348-1

SUSE-SU-2020_1171-1

USN-4235-1

USN-4235-2

Affected Products

Alt Linux

Centos

Apple Macos

Nginx

Red Hat

Suse

Ubuntu

References · 108

• 🔥 https://github.com/0xleft/CVE-2019-20372 · Exploit
• 🔥 https://bertjwregeer.keybase.pub/2019-12-10%20-%20error_page%20request%20smuggling.pdf · Exploit
• https://github.com/nginx/nginx/commit/c1be55f97211d38b69ac0c2027e6812ab8b1b94e · Vendor Advisory
• https://github.com/kubernetes/ingress-nginx/pull/4859 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2023-44487 · Security Note
• http://nginx.org/en/CHANGES · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2024-35200 · Security Note
• https://bdu.fstec.ru/vul/2022-02389 · Security Note
• https://cve.org/CVERecord?id=CVE-2019-20372 · Security Note
• https://osv.dev/vulnerability/USN-4235-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-46463 · Security Note
• https://osv.dev/vulnerability/ALPINE-CVE-2019-20372 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2019-20372 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-4235-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-23419 · Security Note