How severe is CVE-2019-6631?

CVE-2019-6631 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-2019-6631 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6631?

CVE-2019-6631 primarily affects F5 Big-ip Local Traffic Manager. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-6631?

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-2019-6631 published?

CVE-2019-6631 was published on 2019-07-03 and last updated on 2026-06-17.

CVE-2019-6631

CVE-2019-6631 is a high-severity vulnerability in F5 Big-ip Local Traffic Manager 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: F5 Big-ip Local Traffic Manager
Published: 2019-07-03
Last modified: 2026-06-17

Description

On BIG-IP 11.5.1-11.6.4, iRules performing HTTP header manipulation may cause an interruption to service when processing traffic handled by a Virtual Server with an associated HTTP profile, in specific circumstances, when the requests do not strictly conform to RFCs.

Frequently asked questions

What is CVE-2019-6631?: On BIG-IP 11.5.1-11.6.4, iRules performing HTTP header manipulation may cause an interruption to service when processing traffic handled by a Virtual Server with an associated HTTP profile, in specific circumstances, when the requests do not strictly conform to RFCs.
How severe is CVE-2019-6631?: CVE-2019-6631 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-2019-6631 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6631?: CVE-2019-6631 primarily affects F5 Big-ip Local Traffic Manager. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-6631?: 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-2019-6631 published?: CVE-2019-6631 was published on 2019-07-03 and last updated on 2026-06-17.

References

Affected products (13)

cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_analytics:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_domain_name_system:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_edge_gateway:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_global_traffic_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_link_controller:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_policy_enforcement_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_webaccelerator:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_websafe:*:*:*:*:*:*:*:*

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