Description
NGINX before 1.17.7, with certain error_page configurations, allows HTTP request smuggling, as demonstrated by the ability of an attacker to read unauthorized web pages in environments where NGINX is being fronted by a load balancer.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | nginx | 1.16.1-3 | — |
| Debian 13 | nginx | 1.16.1-3 | — |
| Debian 12 | nginx | 1.16.1-3 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | nginx | 1.14.0-0ubuntu1.7 | USN-4235-1 |
| Ubuntu 16.04 LTS | nginx | 1.10.3-0ubuntu0.16.04.5 | USN-4235-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | nginx | 1.4.6-1ubuntu3.9+esm1 | USN-4235-2 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | nginx +7 | 1:1.16.1-1.module+el8.3.0+8844+e5e7039f.1 | RHSA-2020:5495 |
| RHEL 3 | rh-nginx116-nginx +5 | 1:1.16.1-4.el7.1 | RHSA-2020:2817 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | nginx | 1.14.2-6.7.1 | SUSE-SU-2020:0348-1 |
| SLES 15 | nginx | 1.16.1-3.12.7 | SUSE-SU-2020:1171-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 | nginx | 1.16.1-3.12.7 | SUSE-SU-2020:1171-1 |
| SLE HPC 15 | nginx | 1.16.1-3.12.7 | SUSE-SU-2020:1171-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | nginx | 1.21.3-1.4 | openSUSE-SU-2024:11092-1 |
| openSUSE Leap 15.1 | nginx | 1.14.2-lp151.4.6.1 | openSUSE-SU-2020:0204-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | nginx | 1.16.1-r6 | — |
| Alpine v3.23 | nginx | 1.16.1-r6 | — |
| Alpine v3.22 | nginx | 1.16.1-r6 | — |
| Alpine v3.21 | nginx | 1.16.1-r6 | — |
| Alpine v3.20 | nginx | 1.16.1-r6 | — |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | nginx | 1.16.1-r6 | — |
| Alpine v3.18 | nginx | 1.16.1-r6 | — |
| Alpine v3.17 | nginx | 1.16.1-r6 | — |
| Alpine v3.16 | nginx | 1.16.1-r6 | — |
| Alpine v3.15 | nginx | 1.16.1-r6 | — |
| Alpine v3.14 | nginx | 1.16.1-r6 | — |
| Alpine v3.13 | nginx | 1.16.1-r6 | — |
| Alpine v3.12 | nginx | 1.16.1-r6 | — |
| Alpine v3.11 | nginx | 1.16.1-r6 | — |
| Alpine v3.10 | nginx | 1.16.1-r2 | — |
| Alpine v3.9 | nginx | 1.14.2-r5 | — |
| Alpine v3.8 | nginx | 1.14.2-r2 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | nginx +7 | 1:1.16.1-1.0.1.module+el8.3.0+7892+37ea59a5.1 | ELSA-2020-5495 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 3 repositories
-
0xleft/CVE-2019-20372 ★ 6 · Sep 16, 2023
nginx http request smugling error_page directive
-
moften/CVE-2019-20372 ★ 1 · Feb 7, 2025
Nginx CVE-2019-20372 PoC, Unauthenticated File Upload Exploit
-
vuongnv3389-sec/CVE-2019-20372 ★ 0 · Apr 6, 2022
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 13
- RHSA-2020:5495 Red Hat Security Advisory: nginx:1.16 security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2020:2817 Red Hat Security Advisory: rh-nginx116-nginx security update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- USN-4235-1 nginx vulnerability Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-4235-2 nginx vulnerability Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2020:0348-1 Security update for nginx SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0204-1 Security update for nginx SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1171-1 Security update for nginx SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11092-1 nginx-1.21.3-1.4 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SCA-2025-0011 Vulnerabilities affecting Endress+Hauser SSG-E210GC SICK PSIRT · Oct 2, 2025
- SCA-2025-0009 Vulnerabilities affecting SICK TDC-E210GC SICK PSIRT · Aug 1, 2025
- WID-SEC-2023-2481 NGINX: Schwachstelle ermöglicht Manipulation von Daten BSI CERT-Bund (WID) · Nov 3, 2024
- WID-SEC-2024-3320 Moxa Ethernet Switches: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 31, 2024
- ELSA-2020-5495 Moderate: nginx:1.16 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Dec 18, 2020
References
- https://bertjwregeer.keybase.pub/2019-12-10%20-%20error_page%20request%20smuggling.pdf
- http://nginx.org/en/CHANGES
- https://duo.com/docs/dng-notes#version-1.5.4-january-2020
- https://github.com/kubernetes/ingress-nginx/pull/4859
- https://github.com/nginx/nginx/commit/c1be55f97211d38b69ac0c2027e6812ab8b1b94e
- USN-4235-1 vendor-advisory
- USN-4235-2 vendor-advisory
- https://security.netapp.com/advisory/ntap-20200127-0003/
- openSUSE-SU-2020:0204 vendor-advisory
- https://support.apple.com/kb/HT212818
- 20210921 APPLE-SA-2021-09-20-4 Xcode 13 mailing-list