How severe is CVE-2019-11323?

CVE-2019-11323 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2019-11323 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-11323?

CVE-2019-11323 affects Haproxy. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-11323?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-11323 published?

CVE-2019-11323 was published on 2019-05-09 and last updated on 2026-06-17.

CVE-2019-11323

CVE-2019-11323 is a medium-severity vulnerability in Haproxy with a CVSS 3.x base score of 5.9. 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-327.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-327
Affected product: Haproxy
Published: 2019-05-09
Last modified: 2026-06-17

Description

HAProxy before 1.9.7 mishandles a reload with rotated keys, which triggers use of uninitialized, and very predictable, HMAC keys. This is related to an include/types/ssl_sock.h error.

Frequently asked questions

What is CVE-2019-11323?: HAProxy before 1.9.7 mishandles a reload with rotated keys, which triggers use of uninitialized, and very predictable, HMAC keys. This is related to an include/types/ssl_sock.h error.
How severe is CVE-2019-11323?: CVE-2019-11323 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2019-11323 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-11323?: CVE-2019-11323 affects Haproxy. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-11323?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-11323 published?: CVE-2019-11323 was published on 2019-05-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*

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