HOMEVULNERABILITIESCVE-2019-14243
HIGH

CVE-2019-14243

CWE-20Published: July 23, 2019· Updated: Jun 17, 2026

7.5
CVSS v3.1

Official Description

headerv2.go in mastercactapus proxyprotocol before 0.0.2, as used in the mastercactapus caddy-proxyprotocol plugin through 0.0.2 for Caddy, allows remote attackers to cause a denial of service (webserver panic and daemon crash) via a crafted HAProxy PROXY v2 request with truncated source/destination address data.

NVD Source

Technical Analysis

CVE-2019-14243 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.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

haproxy1 product(s)
proxyprotocol
Source: NVD CPE · 1 total CPE entries

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

PATCHhttps://github.com/mastercactapus/proxyprotocol/commit/5c4a101121fc3e868026189c7a73f7f19eef90ac
PATCHhttps://github.com/mastercactapus/proxyprotocol/commit/5c4a101121fc3e868026189c7a73f7f19eef90ac
ADVISORYhttps://caddy.community/t/dos-in-http-proxyprotocol-plugin/6014
ADVISORYhttps://github.com/mastercactapus/caddy-proxyprotocol/issues/8
ADVISORYhttps://github.com/mastercactapus/proxyprotocol/compare/ef496d7...5c4a101
ADVISORYhttps://github.com/mastercactapus/proxyprotocol/issues/1
ADVISORYhttps://github.com/mastercactapus/proxyprotocol/releases/tag/v0.0.2
ADVISORYhttps://caddy.community/t/dos-in-http-proxyprotocol-plugin/6014
ADVISORYhttps://github.com/mastercactapus/caddy-proxyprotocol/issues/8
ADVISORYhttps://github.com/mastercactapus/proxyprotocol/compare/ef496d7...5c4a101
ADVISORYhttps://github.com/mastercactapus/proxyprotocol/issues/1
ADVISORYhttps://github.com/mastercactapus/proxyprotocol/releases/tag/v0.0.2

All References (12)

→
https://caddy.community/t/dos-in-http-proxyprotocol-plugin/6014Third Party Advisory
→
https://github.com/mastercactapus/caddy-proxyprotocol/issues/8Issue Tracking · Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/commit/5c4a101121fc3e868026189c7a73f7f19eef90acPatch · Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/compare/ef496d7...5c4a101Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/issues/1Exploit · Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/releases/tag/v0.0.2Release Notes · Third Party Advisory
→
https://caddy.community/t/dos-in-http-proxyprotocol-plugin/6014Third Party Advisory
→
https://github.com/mastercactapus/caddy-proxyprotocol/issues/8Issue Tracking · Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/commit/5c4a101121fc3e868026189c7a73f7f19eef90acPatch · Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/compare/ef496d7...5c4a101Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/issues/1Exploit · Third Party Advisory
→
https://github.com/mastercactapus/proxyprotocol/releases/tag/v0.0.2Release Notes · Third Party Advisory

Quick Facts

CVE IDCVE-2019-14243
CVSS Score7.5 / 10
SeverityHIGH
WeaknessCWE-20
CISA KEVNo
Affected1 vendor(s)
PublishedJul 23, 2019

Related CVEs (CWE-20)

CVE-2007-0213
10.0
CVE-2011-0923
10.0
CVE-2025-23202
10.0
CVE-2025-34060
10.0
CVE-2003-1425
10.0
CVE-2007-4915
10.0

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2019-14243 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.
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