How severe is CVE-2019-14243?

CVE-2019-14243 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-14243 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-14243?

CVE-2019-14243 affects Haproxy Proxyprotocol. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-14243?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-14243 published?

CVE-2019-14243 was published on 2019-07-23 and last updated on 2026-06-17.

CVE-2019-14243

CVE-2019-14243 is a high-severity vulnerability in Haproxy Proxyprotocol with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 4% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Haproxy Proxyprotocol
Published: 2019-07-23
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2019-14243?: 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.
How severe is CVE-2019-14243?: CVE-2019-14243 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-14243 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-14243?: CVE-2019-14243 affects Haproxy Proxyprotocol. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-14243?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2019-14243 published?: CVE-2019-14243 was published on 2019-07-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:haproxy:proxyprotocol:*:*:*:*:*:caddy:*:*

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