MEDIUM
CVE-2019-20372
CWE-444Published: January 9, 2020· Updated: Jun 17, 2026
5.3
CVSS v3.1
Official 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.
Technical Analysis
CVE-2019-20372 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityLow
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Affected Vendors & Products
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
ADVISORYhttp://nginx.org/en/CHANGES
ADVISORYhttps://usn.ubuntu.com/4235-1/
ADVISORYhttps://usn.ubuntu.com/4235-2/
ADVISORYhttp://nginx.org/en/CHANGES
ADVISORYhttps://usn.ubuntu.com/4235-1/
ADVISORYhttps://usn.ubuntu.com/4235-2/
All References (22)
→
http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00013.htmlMailing List · Third Party Advisory
→
http://nginx.org/en/CHANGESMitigation · Release Notes · Vendor Advisory
→
http://seclists.org/fulldisclosure/2021/Sep/36Mailing List · Third Party Advisory
→
https://bertjwregeer.keybase.pub/2019-12-10%20-%20error_page%20request%20smuggling.pdfExploit · Mitigation · Third Party Advisory
→
https://duo.com/docs/dng-notes#version-1.5.4-january-2020Release Notes · Third Party Advisory
→
https://github.com/kubernetes/ingress-nginx/pull/4859Patch · Third Party Advisory
→
https://github.com/nginx/nginx/commit/c1be55f97211d38b69ac0c2027e6812ab8b1b94ePatch · Vendor Advisory
→
https://security.netapp.com/advisory/ntap-20200127-0003/Third Party Advisory
→
https://support.apple.com/kb/HT212818Third Party Advisory
→
https://usn.ubuntu.com/4235-1/Third Party Advisory
→
https://usn.ubuntu.com/4235-2/Third Party Advisory
→
http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00013.htmlMailing List · Third Party Advisory
→
http://nginx.org/en/CHANGESMitigation · Release Notes · Vendor Advisory
→
http://seclists.org/fulldisclosure/2021/Sep/36Mailing List · Third Party Advisory
→
https://bertjwregeer.keybase.pub/2019-12-10%20-%20error_page%20request%20smuggling.pdfExploit · Mitigation · Third Party Advisory
Quick Facts
CVE IDCVE-2019-20372
CVSS Score5.3 / 10
SeverityMEDIUM
WeaknessCWE-444
CISA KEVNo
Affected5 vendor(s)
PublishedJan 9, 2020
Related CVEs (CWE-444)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2019-20372 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.