How severe is CVE-2019-6681?

CVE-2019-6681 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-2019-6681 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6681?

CVE-2019-6681 affects F5 Big-ip Local Traffic Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-6681?

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-2019-6681 published?

CVE-2019-6681 was published on 2019-12-23 and last updated on 2026-06-17.

CVE-2019-6681

CVE-2019-6681 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. The underlying weakness is classified as CWE-401.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-401
Affected product: F5 Big-ip Local Traffic Manager
Published: 2019-12-23
Last modified: 2026-06-17

Description

On BIG-IP versions 15.0.0-15.0.1.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, and 12.1.0-12.1.5, a memory leak in Multicast Forwarding Cache (MFC) handling in tmrouted.

Frequently asked questions

What is CVE-2019-6681?: On BIG-IP versions 15.0.0-15.0.1.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, and 12.1.0-12.1.5, a memory leak in Multicast Forwarding Cache (MFC) handling in tmrouted.
How severe is CVE-2019-6681?: CVE-2019-6681 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-2019-6681 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6681?: CVE-2019-6681 affects F5 Big-ip Local Traffic Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-6681?: 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-2019-6681 published?: CVE-2019-6681 was published on 2019-12-23 and last updated on 2026-06-17.

References

https://support.f5.com/csp/article/K93417064

Affected products (1)

cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*

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